Midterm Exam 1

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As a solid element melts, the atoms become __________ and they have __________ attraction for one another.

more separated, less

Units of the rate constant of a reaction _____ independent of the overall reaction order.

are not

When table salt is dissolved in water, the salt is the: a. solution b. solute c. solvent

b (solute)

In general, as temperature goes up, reaction rate

goes up regardless of whether the reaction is exothermic or endothermic

rate

means instantaneous rate during a trip for example the instantaneous speed at any moment is the speedometer reading at that moment

metal ions act as Lewis acids and form complex ions with Lewis bases in the solvent.

metal-ligand complexes

strong acid

readily donates a proton forming a WEAK conjugate base HCl -strong base Cl- - weak c.b

ligand

an attached Lewis base that forms a complex ion

Which one of the following is a Bronsted-Lowry base?

(CH3)3N

Of the following, the entropy of ____ is the largest.

HI (g)

Of the following which is the strongest acid?

HIO4

When the solvent is water, the interaction is called -------

Hydration

What is the major intermolecular force between water molecules?

Hydrogen Bonding

The electrode at which oxidation occurs is called the

anode

Of the concentration units below, only __________ is temperature dependent.

molarity

Molar solubility is the number of ______ ___ _______ dissolving to form a ______ of saturated solution.

moles of solute; liter

Molality is defined as the __________.

moles solute/kg solvent

rate law

an equation that shows how the rate depends on reactant concentrations

strong electrolyte

completely ionizes in water

lewis acids are

electron pair acceptors

pH or pOH = 7 .....

neutral

34. Which one of the following concentration units varies with temperature?

(A) molarity

The kinetics of the reaction below were studied and it was determined that the reaction rate did not change when the concentration of B was tripled. The reaction is __________ order in B. A + B --> products

zero

A flask is charged with 0.124 mol of A and allowed to react to form B according the the reaction A(g) → B(g). The following data are obtained for [A] as the reaction proceeds: Time(s) 0.00 10.00 20.0 30.0 40.0 Moles of A 0.124 0.110 0.088 0.073 0.054 How many moles of B are present at 10s?

0.014

In which of the following aqueous solutions would you expect AgCl to have the lowest solubility ?

0.020 M BaCl2

The equilibrium constant for reaction 1 is K. The equilibrium constant for reaction 2 is what? (1 SO₂ (g) + (1/2)O₂ ↔ SO₃ (g) (2 2SO₃ (g) ↔ 2SO₂ (g) + O₂ (g)

1/K²

The overall order of a reaction is 2. The units of the rate constant for the reaction are _________.

1/Ms

The Ka for HCN is 4.9 x 10^-10. What is the value of Kb for CN-?

2.0 x 10^-5

A flask is charged with 0.124 mol of A and allowed to react to form B according to the reaction A(g) \longrightarrow B(g). The following data are obtained for [A] as the reaction proceeds: Time (s) 0.00 10.0 20.0 30.0 40.0 Moles of A 0.124 0.110 0.086 0.073 0.054 The average rate of disappearance of A between 10 s and 20 s is ____ mol/s.

2.2 x 10^-3

29) Classify the following compounds as weak bases (W) or strong bases (S): methylamine carbonate ion potassium hydroxide A) W W S B) S S S C) S W W D) W S S E) W S W

A) W W S

The equilibrium constant for the gas phase reaction 2NH3 (g) <--> N2 (g) + 3H2 (g) is Keq = 230 at 300 °C. At equilibrium, __________. A) products predominate B) reactants predominate C) roughly equal amounts of products and reactants are present D) only products are present E) only reactants are present

A

Which one of the following will change the value of an equilibrium constant? A) changing temperature B) adding other substances that do not react with any of the species involved in the equilibrium C) varying the initial concentrations of reactants D) varying the initial concentrations of products E) changing the volume of the reaction vessel

A

Consider the following reaction at equilibrium: 2NH₃ (g) ↔ N₂ (g) +3H₂ (g) delta H° = +92.4 kj Le Chatelier's principle predicts that adding N₂ (g) to the system at equilibrium will result in _____.

A decrease in the concentration of H₂ (g)

4. A 0.100 m solution of which one of the following solutes will have the lowest vapor pressure? A) KClO4 B) Ca(ClO4)2 C) Al(ClO4)3 D) sucrose E) NaCl

C. Al(ClO4)3

A 0.1 M aqueous solution of __________ will have a pH of 7.0 at 25.0 °C. NaOCl , KCl , NH4Cl , Ca(OAc)2 A) NaOCl B) KCl C) NH4Cl D) Ca(OAc)2 E) KCl and NH4Cl

B

Calculate the mole fraction of nitric acid of a 17.5% (by mass) aqueous solution of nitric acid. A) 3.37 B) 0.0572 C) 0.278 D) 0.0607 E) 1.75

B) 0.0572

Oxidation Numbers BaO₂

Ba= 2+ O= 1-

Delta S is positive for the reaction _____.

BaF2 (s) --> Ba^2+ (aq) + 2F- (aq)

A 0.0035 M aqueous solution of a particular compound has pH = 2.46. The compound is __________. A) a weak base B) a weak acid C) a strong acid D) a strong base E) a salt

C

A 0.1 M solution of __________ has a pH of 7.0. A) Na2S B) KF C) NaNO3 D) NH4Cl E) NaF

C

Which one of the following substances would be the most soluble in CCl4?

C10H22

Substance that increases the rate of a r x n w/out undergoing a net chemical change itself =

Catalyst; (does so by providing a different mechanism for the r x n, one that has a lower activation energy.) (Catalysts affect the speed at which equilibrium is reached but do not affect the magnitude of K)

Using the data in the table, which of the conjugate bases below is the strongest base?

ClO-

A 0.0035-M aqueous solution of a particular compound has pH = 2.46. The compound is __________ . A) a strong base B) a weak acid C) a weak base D) a strong acid

D

A Br0nsted-Lowry base is defined as a substance that __________. A) increases [H+] when placed in H2O B) decreases [H+] when placed in H2O C) increases [OH-] when placed in H2O D) acts as a proton acceptor E) acts as a proton donor

D

The most likely van't Hoff factor for an 0.01 m CaI₂ solution is: A) 1.27 B) 3.29 C) 1.00 D) 2.69 E) 3.00

D) 2.69

2) Consider a solution containing 0.100 M fluoride ions and 0.126 M hydrogen fluoride. The concentration of fluoride ions after the addition of 5.00 mL of 0.0100 M HCl to 25.0 mL of this solution is __________ M. A) 0.0850 B) 0.00167 C) 0.0980 D) 0.0817 E) 0.00253

D) 0.0817

Of the acids in the table below, _________ is the strongest acid.

HF

Of the following substances, an aqueous solution of __________ will form basic solutions. NaHS , Cu(NO3)2 , KHCO3 , NaF A) NaHS , Cu(NO3)2 B) KHCO3 NaHS C) NaF only D) NaF, E) NaHS, KHCO3 and NaF

E

Formation of solutions where the process is endothermic can be spontaneous provided that: A) the solvent is a gas and the solute is a solid B) they are accompanied by another process that is exothermic C) they are accompanied by an increase in order D) the solvent is water and the solute is a gas E) they are accompanied by an increase in disorder

E) they are accompanied by an increase in disorder

Which of the following is a Bronsted-Lowry Acid? A. CH₃COOH B. HNO₂ C. (CH₃)₃NH+ D. HF E. All of the above

E. All of the above

8. The order of a reaction: a) Is determined by the stoichiometry of the reaction b) Is determined by the physical states of the reactants c) Depends on the activation energy of the reactants d) Depends on the temperature of the reaction e) Is determined by and depends on all of the above f) Is determined by and depends on none of the above

F. Is determined by and depends on of the above

Identify the acid, base, conjugate acid, and conjugate base in the following reactions. HF + H20 <----> H3O^(+) + F^9-)

HF= acid H2O= Base H3O= Conjugate Acid F= conjugate base

seven strong bases

HI HBr HCl H2SO4 HClO4 HClO3 HNO3

N2(g) + 3H2(g)<--> 2NH3(g) equilibrium r x n is basis for =

Haber Process for production of Amonia

The solubilities of gases in a liquid are generally proportional to the pressure of the gas over the soln. expressed by -----

Henry's Law Sg = kPg

Relationship btwn the concentrations of reactants and products of a system at equilibrium is given by =

Law of Mass Action

Identify the acid, base, conjugate acid, and conjugate base in the following reactions. NH3 + H2O <---> OH^(-) + NH4^(+)

NH3= base H2O =acid OH= conjugate base NH4= conjugate acid

1) What is the conjugate acid of ? A) NH3 B) NH2- C) NH3- D) NH4+ E) NH4OH

NH4+

What is the conjugate acid of NH3?

NH4+

Which transformation could take place at the anode of an electrochemical cell?

NO ----> NO3^-

The addition of hydrofluoric acid and __________ to water produces a buffer solution.

NaF

3.0 × 10-3

The concentration of iodide ions in a saturated solution of lead (II) iodide is __________ M. The solubility product constant of PbI2 is 1.4 × 10-8.

+1

The following reaction occurs in aqueous solution: (see photo) NH₄⁺ (aq) + NO₂⁻ → N₂ (g) + 2H₂O (l) The data below is obtained at 25 °C. The order of the reaction in NH4+ is ________. A) -2 B) -1 C) +2 D) +1 E) 0

zero

The kinetics of the reaction below were studied and it was determined that the reaction rate did not change when the concentration of B was tripled. The reaction is ________ order in B. A + B → P A) zero B) first C) second D) third E) one-half

activation energy

The minimum energy to initiate a chemical reaction is the ________.

Boyle's Law

The relationship between the pressure and volume of a gas at constant temperture; when volume increase, pressure decreases. One gets smaller as the other gets bigger. (P₁V₁=P₂V₂) (V= constant x 1/P or PV = constant)

Which salt when dissolved up in water will have a pH of 7.0? a. KCl b. NH4Cl c. NaBrO d. KF

a. KCl

CH3OH is extremely soluble in water but CH3CH2CH2CH2CH2CH2OH has very low solubility. WHY?

The second compound is quite nonpolar and interacts primarily by dispersion forces while CH3OH is dominated by H-bonding

Classify the following compounds as weak acids (W) or strong acids (S): hydrocyanic hydrofluroic phenol

WWW

How many isomers (constitutional and stereoisomers) exist for dimethylpentane? a. 2 b. 3 c. 4 d. 5

c

Rates of reaction _______ be positive or negative.

cannot

Nitrogen fixation is a difficult process because ____.

nitrogen is a very unreactive, largely due to its triple bond

alkaline earth metals have ...... on pH

no affect

Ammonia is a ____________.

weak base

40. Which of the following liquids will have the lowest freezing point?

(E) aqueous KF (0.50 m)

Acid (HA)-----> conjugate base(A-)

-----> -H+

Of the following solutions, which has the greatest buffering capacity? a. 0.821MHFand0.217MNaF b. 0.821MHF and 0.909 M NaF c. 0.100 M HF and 0.217 M NaF d. 0.121 M HF and 0.667 M NaF e. They are all buffer solutions and would all have the same capacity.

0.821MHF and 0.909 M NaF

Dinitrogentetraoxide partially decomposes according to the following equilibrium: N2O4 (g) = 2 NO2 (g) A 1.00-L flask is charged with 0.0400 mol of N2O4. At equilibrium at 373 K, 0.0055 mol of N2O4 remains. Keq for this reaction is ____.

0.87

Consider the reaction N2(g) + O2(g) --><--2 NO(g) Kc=0.10 Predict the direction of the reaction if we start with 4.0 mol N2, 1.0 mol O2 and 0.80 mol of NO in a 20 L container =

1. Calculate concentrations N2= 4.0/20.0 = 0.20 M O2 = 1.0/20.0 = 0.05 M NO = 0.80/20.0 = 0.04 M 2. Calculate Q = [NO]_0^2/[N2][O2] = (0.04)/(0.20)(0.05) = 0.16 3. Compare Q and K. Note Q>K so reaction will shift to the left

The molar concentration of hydronium ion in pure water at 25 °C is _____.

1.0 x 10^-7

A solution contains 28% phosphoric acid by mass. This means that ____.

100 g of this solution contains 28 g of phosphoric acid

Calculate the pOH of a solution at 25 °C that contains 1.94 x 10^-10 M hydronium ions.

4.29

Calculate the concentration (in M) of hydroxide ions in a solution at 25.0 °C with a pOH of 4.223.

5.98 x 10^-5

What is the pH of an aqueous solution at 25.0 °C that contains 3.98 × 10-9 M hydronium ion?

8.400

Which substance in the reaction below either appears or disappears the fastest? 4NH3 + 7O2 → 4NO2 + 6H2O A) O2 B) NH3 C) H2O D) NO2 E) The rates of appearance/disappearance are the same for all of these.

A

Which one of the following vitamins is water soluble? A) A B) B C) K D) D E) E

A) A Vitamin C is also water soluble

Which one of the following will change the value of an equilibrium constant?

A. Changing temperature

Reaction rate data showing temperature dependence obey an equation devised by _________.

Arrhenius

The hydride ion, H- , is a stronger base than the hydroxide ion, OH- . The product(s) of the reaction of hydride ion with water is/ are __________. A) H3O+ (aq) B) OH- (aq) + H2 (g) C) OH- (aq) + 2H+ (aq) D) no reaction occurs E) H2O2 (aq)

B

The molar concentration of hydronium ion in pure water at 25 °C is __________. A) 0.00 B) 1.0 x 10-7 C) 1.0 x 10-14 D) 1.00 E) 7.00

B

Ammonia is a __________. A) weak acid B) strong base C) weak base D) strong acid E) salt

C

25) Ammonia is a __________.

C) weak base

Which one of the following derivatives of ethane has the highest boiling point?

C2I6

Which of the following ions will act as a weak base in water?

ClO-

Of the following, which is the strongest acid? A) HClO B) HClO3 C) HClO2 D) HClO4 E) HIO

D

21) The pH of a solution prepared by mixing 45.0 mL of 0.183 M KOH and 65.0 mL of HCl is __________. A) 1.314 B) 2.923 C) 0.744 D) 1.966 E) 7.148

D) 1.966

7. The graph shown below depicts the relationship between concentration and time for the following chemical reaction. The slope of this line is equal to __________. A) k B) −1/ k C) o ln[A] D) −k E) 1/ k

D. -k

Kc

Kc = mol/L - molarity Kc = Kf/Kr

When equilibrium system of interest consists of gases - convenient to express the concentrations of reactants and products in terms of gas pressure:

Kp = (P_D)^d(P_E)^e/(P_A)^a(P_B)^b Kc and Kp are related by expression: Kp = Kc(RT) raised to the delta n

Oxidation Numbers MnO4⁻

Mn= 7+ O= 2-

the addition of hydrofluoric acid and ______ to water produces a buffer solution. HCl NaNO3 NaF NaCl NaBr

NaF

he equilibrium constant for the gas phase reaction N2 (g) + 3H2 (g) 2NH3 (g) is Keq = 4.34 × 10-3 at 300 °C. At equilibrium, ________.

Reactants predominate

Same Phase: Gas in Gas = (air) Solvent = Liquid in a Liquid = Alcohol in water> Solvent = Solid in Solid = Brass

Solvent = (g) in (g) --> Nitrogen Solvent = (l) in (l) --> Depends on which of the two is in the highest [ ]. Solvent = (s) in (s) --> Zn in Cu

1/s

The overall order of a reaction is 1. The units of the rate constant for the reaction are ________. A) M/s B) M⁻¹ s⁻¹ C) 1/s D) 1/M E) s/M₂

M⁻¹ s⁻¹

The overall order of a reaction is 2. The units of the rate constant for the reaction are ________. A) M/s B) M⁻¹ s⁻¹ C) 1/s D) 1/M E) s/M₂

hydrogen bonding

The predominant intermolecular force in (CH3)2NH is __________.

dipole-dipole forces

The predominant intermolecular force in AsH3 is

28

The value of Keq for the equilibrium H2 (g) + I2 (g) 2 HI (g) is 794 at 25 °C. What is the value of Keq for the equilibrium below?

Which of the following compounds is a meso compound? a. (2R,3R)-dibromobutane b. (2R,3S)-dibromobutane c. (2R,3S)-3-bromo-2-butanol d. (2R,3R)-3-bromo-2-butanol

b

Which of the following is the strongest acid? a. HCl b. HI c. HF d. HBr

b

Which of the following is the strongest base? a. iodide anion, I− b. fluoride anion, F− c. bromide anion, Br− d. chloride anion, Cl−

b

pOH < 7

basic

The entropy of the universe is ____.

continually increasing

Solubility is _________ when a common ion is added.

decreased

The ionization of a weak base is also .... by the addition of a common ion.

decreased

lewis bases are

electron pair donors

An unsaturated solution is one that ____.

has a concentration lower than the solubility

Decreasing pressure ________ volume, and favors _________.

increases, reactants

If a reaction is the sum of two or more r x n's

its equilibrium constant will be the product of the equilibrium constants for the individual reactions.

If the rate law for the reaction 2A + 3B --> products is second order in A and first order in B, then the rate law is rate = ___.

k[A]^2[B}

large value of k (10⁹ or higher) indicates..... small value of k (10 or lower) indicates....

means a fast reaction slow reaction

An alloy is a

metallic material that is composed of two or more elements.

PH

negative logarithm in base 10 of [H+]

if [H3O+] = 1.0 x 10^-7 M then the solution is

neutral

blue pH indicator

phenolphthalein indicator is good between ranges between 8.3-10

Which of the following liquids will have the highest freezing point?

pure H2O

In which of the following aqueous solutions would you expect AgBr to have the highest solubility? a. 0.10 M LiBr b. 0.10 M AgNO3 c. 0.20 M NaBr d. 0.15 M KBr e. pure water

pure water

reaction orders

the exponents m and n in the rate lw formula

initial pH

the pH of the solution before the addition of any base

Bronsted-Lowry acid and bases

transfer of H+ ions from one substance to another

for a series of oxyacids acidity increases

with the increase of O

pOH =

- log [OH-] and [OH-] = 10-pOH

Hydrophillic

...

Hydrophobic

...

50) Of the following, which is the weakest acid? A) HIO B) HIO4 C) HIO2 D) HIO3 E) The acid strength of all of the above is the same.

A) HIO

24) Classify the following compounds as weak acids (W) or strong acids (S): hypochlorous acid perchloric acid chloric acid A) W S S B) S S S C) S W W D) W W W E) W S W

A) W S S

Hydration is a specific example of the phenomenon known generally as: A) solvation B) dilution C) disordering D) condensation E) salutation

A) solvation

Of the following acids, ____ is not a strong acid. A. HNO₂ B. H₂SO₄ C. HNO₃ D. HClO₄ E. HCl

A. HNO₂

The minimum amount of energy required for a reaction to occur is called -

Activation energy, Ea

has a concentration lower than the solubility

An unsaturated solution is one that __________.

The solubility of nitrogen gas at 25 °C and 1 atm is 6.8 x 10-4 mol/L. If the partial pressure of nitrogen gas in air is 0.76 atm, what is the concentration (molarity) of dissolved nitrogen? A) 4.9 x 10-4 M B) 5.2 x 10-4 M C) 1.1 X 10-5 M D) 6.8 x 10-4 M E) 3.8 x 10-4 M

B) 5.2 x 10-4 M

5) The Kb of ammonia is . The pH of a buffer prepared by combining 50.0 mL of 1.00 M ammonia and 50.0 mL of 1.00 M ammonium nitrate is __________. A) 4.63 B) 9.25 C) 4.74 D) 9.37 E) 7.00

B) 9.25

The expression for Kp for the reaction below is __________. 4CuO (s) + CH4 (g) <--> CO2 (g) + 4Cu (s) + 2H2O (g) A) PCH4 / PCO2PH2^2 B) [Cu]PCO2PH2O^2 / [CuO]^4 PCH4 C) PCO2PH2O^2 / PCH4 D) PCO2PH2O^2 / PCuO E) PCH4 / PH2O^2PCO2

C

When a chemical r x n achieves a state in which the forward and revers processes are occurring at same rate is the =

Chemical Equilibrium (results in formation of an equilibrium mixture of reactants and products of r x n) composition of an equilibrium mixture does not change with time if temperature is held constant.

Which one of the following is the weakest acid? A) HF (Ka = 6.8 x 10-4) B) HClO (Ka = 3.0 x10-8) C) HNO2 (Ka = 4.5 x 10-4 D) HCN (Ka = 4.9 x 10-10) E) Acetic acid (Ka = 1.8 x 10-5)

D

3) A Br nsted-Lowry acid is defined as a substance that __________.

E) acts as a proton donor

they are accompanied by an increase in disorder

Formation of solutions where the process is endothermic can be spontaneous provided that

For reaction where overall reaction order is 2, k has units

M-1 s-1

neutral solution

[H3O+] = [OH-] = Kw = 1.0 X 10^-7 M at 25 Celsius

basic solution

[H3O+]<[OH-]; and [H3O+]<1.0X10^-7M and [OH-]>1.0X10^-7 M at 25 Celsius

14) Of the following acids, __________ is not a strong acid. A) HNO2 B) H2SO4 C) HNO3 D) HCIO4 E) HCl

a. HNO2

if [H3O+] > [OH-] then the solution is

acidic

Which of the following liquids will have the lowest freezing point?

aqueous FeI3 (0.24 m)

What is the approximate pKa value of acetic acid? a. −7 b. 5 c. 16 d. 51

b

at 1000 K, the equilibrium constant for the reaction 2NO (g) + Br₂ (g)↔2NOBr (g) is Kp = 0.013. Calculate Kp for the reverse reaction. 2NOBr ↔ 2NO (g) + Br₂ (g) a. 0.013 b. 1.6 x 10⁻⁴ c. 77 d. 0.99

c. 77

Which of the following are redox reactions I. PCl₃ + Cl₂ → PCl₅ II. Cu + 2AgNO₃ → Cu(NO₃)₂ III. CO₂ + 2LiOh → Li₂CO₃ + H₂O IV FeCl₂ + 2NaOH → Fe(OH)₂ + 2NaCl a. III b. IV c. I and II d. I, II, and III e. I, II, III, and IV

c. I and II

A reversible process is one that ____.

can be reversed with no net change in either system or surroundings

An assembly of a metal ion and the Lewis bases bonded to it is called a __________.

complex ion

If a substance is added to a system at equilibrium, the system reacts to _________ some of the substance.

consume

Redox reactions involve the ____ of electrons a. combining b. sharing c. substitution d. transfer

d. transfer

buffers in the blood

hyperventilation

The reaction below is exothermic: 2SO₂ (g) + O₂ (g) ↔ 2SO₃ (g) Le Chatelier's principle predicts that _______ will result in an increase in the number of moles of SO₃ (g) in the reaction container.

increasing the pressure

Heat + NH₄Cl (s) ↔ NH₃ (g) + HCl (g) If the concentration of NH₃ is increased, will the reaction shift to the right, left, or no change

left

Increasing T in an exothermic reaction causes the equilibrium to shift _____.

left

if [H3O+] = [OH-] then the solution is

neutral

K(sp) stands for

solubility product

Together, liquids and solids constitute __________ phases of matter.

the condensed

On a phase diagram, the melting point is the same as __________.

the freezing point

which of solutions will form a buffer solution

the one that has a WEAK acid and its conjugate base present!

pH range of any buffer is

the pH range over which the buffer acts effectively. When the concentration of weak acid and conjusgate base are equal pH = pK(a)

equivalence point

the stoichiometric amount of acid equals that of the base

Changing the temperature will change the value of an equilibrium constant

true

A reaction that is spontaneous as written ____.

will proceed without outside intervention

The pH range of a buffer is usually...?

within +- one pH unit os the pKa

27. The solubility of nitrogen gas at 25 °C and 1 atm is 6.8 ⋅ 10-4 mol/L. If the partial pressure of nitrogen gas in air is 0.76 atm, what is the concentration (molarity) of dissolved nitrogen? Use Henry's law.

(A) 5.2 x 10-4 M

24. Which one of the following substances is more likely to dissolve in CCl4?

(A) CBr4

25. Which one of the following is most soluble in water?

(A) CH3OH

What is the oxidation number of bromine in the BrO3- ion?

+5

Base (B) -------> conjugate acid (BH+)

--------> +H+

give an expression that relates the rate of disappearance of each reactant to the rate of appearance of each product. 2 H2 + O2 --------> 2 H2O

-1/2∆[H2]/∆t = -∆[O2] / ∆t = 1/2∆ [H2O] / ∆t

give an expression that relates the rate of disappearance of each reactant to the rate of appearance of each product. N2 + 3 H2 --------> 2 NH3

-∆[N2] / ∆t = -1/3∆[H2]/∆t= ∆1/2[NH3] / ∆t

t_1/2 = >

0.693/k This equation caculates the time required for the reactant concentration to drop to half its initial value. In other words, it calculates the half-life.

Consider the following equilibrium. 2 SO2 (g) + O2 (g) 2 SO3 (g) The equilibrium cannot be established when ________ is/are placed in a 1.0-L container.

0.75 mol SO2 (g)

Consider the following equilibrium. 2SO₂ (g) + O₂ (g) ↔ 2SO₃ (g) The equilibrium cannot be established when ______ is/are placed in a 1.0 L container.

0.75 mol SO₂ (g)

Of the following solutions, which has the greatest buffering capacity? a. 0.521 M HC2H3O2 and 0.217 M NaC2H3O2 b. 0.821 M HC2H3O2 and 0.713 M NaC2H3O2 c. 0.365M HC2H3O2 and 0.497 M NaC2H3O2 d. 0.121 M HC2H3O2 and 0.116 M NaC2H3O2

0.821 M HC2H3O2 and 0.713 M NaC2H3O2

The acid-dissociation constants of phosphoric acid (H3PO4) are Ka1 = 7.5 × 10^-3 Ka2 = 6.2 × 10^-8 , and Ka3 = 4.2 × 10^-13 at 25.0 °C. What is the pH of a 2.5 M aqueous solution of phosphoric acid?

0.88

The acid-dissociation constants of sulfurous acid (H2SO3 ) are Ka1 = 1.7 × 10^-2 and Ka2 = 6.4 × 10^-8 at 25.0 °C. Calculate the pH of a 0.163 M aqueous solution of sulfurous acid.

1.30

Potassium metal crystallizes in a body-centered cubic structure with a unit cell edge length of 5.31 Å. The radius of a potassium atom is __________ Å.

2.30

At elevated temperatures, dinitrogen pentoxide decomposes to nitrogen dioxide and oxygen: 2N₂O₅ (g) → 4NO₂ (g) + O₂ (g) When the rate of formation of NO₂ is 5.5 x 10⁻⁴ M/s, the rate of decomposition of NO

2.8 x 10⁻⁴

The rate constant of a first-order process that has a half-life of 3.50 min is __________ s^-1.

3.30 x 10^-3

The half-life of a first-order reaction is 13 min. If the initial concentration of reactant is 0.085 M, it takes _____ min for it to decrease to 0.055 M.

8.2

Of the following, which is the weakest acid? A) HIO B) HIO4 C) HIO2 D) HIO3 E) The acid strength of all of the above is the same.

A

The equilibrium-constant expression depends on the __________ of the reaction. A) stoichiometry B) mechanism C) stoichiometry and mechanism D) the quantities of reactants and products initially present E) temperature

A

increases by a factor of 4

A reaction was found to be second order in carbon monoxide concentration. The rate of the reaction ________ if the [CO] is doubled, with everything else kept the same. A) doubles B) remains unchanged C) triples D) increases by a factor of 4 E) is reduced by a factor of 2

decreases, decreases

As the concentration of a solute in a solution increases, the freezing point of the solution __________ and the vapor pressure of the solution __________.

reactant molecules collide more frequently and with greater energy per collision

As the temperature of a reaction is increased, the rate of the reaction increases because the ________. A) reactant molecules collide less frequently B) reactant molecules collide more frequently and with greater energy per collision C) activation energy is lowered D) reactant molecules collide less frequently and with greater energy per collision E) reactant molecules collide more frequently with less energy per collision

What is the order of the reaction with respect to OH-? A) 0 B) 1 C) 2 D) 3 E) 4

B

Which one of the following is true concerning the Haber process? A) It is a process used for shifting equilibrium positions to the right for more economical chemical synthesis of a variety of substances. B) It is a process used for the synthesis of ammonia. C) It is another way of stating LeChatelier's principle. D) It is an industrial synthesis of sodium chloride that was discovered by Karl Haber. E) It is a process for the synthesis of elemental chlorine.

B

The solubility of nitrogen gas in water at 25 °C and a nitrogen pressure of 1.0 atm is 6.9 ×10⁻⁴ M. The solubility of nitrogen in water at a nitrogen pressure of 5.0 atm is __________ M. A) .00086 B) 0.0035 C) 5.0 D) 0.00055 E) 120

B) 0.0035

49) Of the following, which is the strongest acid? A) HIO B) HIO4 C) HIO2 D) HIO3 E) The acid strength of all of the above is the same.

B) HIO4

Of the compounds below, a 0.1 M aqueous solution of ____ will have the highest pH. A. NaClO, Ka of HClO = 3.2 x 10⁻⁸ B. KCN, Ka of HCN = 4.0 x 10⁻⁷ C. NaHS, Kb of HS⁻ = 1.8 x 10⁻⁷ D. NaOAc, Ka of HOAc = 1.8 x 10⁻⁵ E. NH₄NO₃, Kb of NH₃ = 1.8 x 10⁻⁵

B. KCN, Ka of HCN = 4.0 x 10⁻⁷

Ammonia is a ________. A. Weak Acid B. Weak Base C. Salt D. Strong Acid E. Strong Base

B. Weak Base

The absorption of electromagnetic radiation by a substance at a particular wavelength is directly proportional to its concentration

Beer's Law

The relationship of absorbed light to the concentration of the substance absorbing the light is governed by __________.

Beer's law

) In general, as temperature goes up, reaction rate __________. A) goes up if the reaction is exothermic B) goes up if the reaction is endothermic C) goes up regardless of whether the reaction is exothermic or endothermic D) stays the same regardless of whether the reaction is exothermic or endothermic E) stays the same if the reaction is first order

C

Consider the following reaction at equilibrium. 2CO2 (g) <--> 2CO (g) + O2 (g) ΔH° = -514 kJ Le Chatelier's principle predicts that the equilibrium partial pressure of CO (g) can be maximized by carrying out the reaction __________. A) at high temperature and high pressure B) at high temperature and low pressure C) at low temperature and low pressure D) at low temperature and high pressure E) in the presence of solid carbon

C

Consider the following reaction at equilibrium: 2CO2 (g) <--> 2CO (g) + O2 (g) ΔH° = -514 kJ Le Chatelier's principle predicts that an increase in temperature will __________. A) increase the partial pressure of O2 (g) B) decrease the partial pressure of CO2 (g) C) decrease the value of the equilibrium constant D) increase the value of the equilibrium constant E) increase the partial pressure of CO

C

Which of the following aqueous solutions has the lowest [OH-]? A) a solution with a pH of 3.0 B) a 1 x 10-4 M solution of HNO3 C) a solution with a pOH of 12.0 D) pure water E) a 1 x 10-3 M solution of NH4Cl

C

Calculate the mole fraction of phosphoric acid (H₃PO₄) in a 25.4% (by mass) aqueous solution. A) 0.0626 B) 4.14 C) 0.0589 D) 1.00 E) 0.259

C) 0.0589

4) A substance that is capable of acting as both an acid and as a base is __________.

C) amphoteric

Which of the following expressions is the correct equilibrium-constant expression for the reaction below? HF (aq) + H2O (l) <--> H3O+ (aq) + F- (aq) A) [HF][H2O] / [H3O+][F-] B) 1 / HF C) [H3O+][F-] / [HF][H2O] D) [H3O+][F-] / [HF] E) [F-] / [HF]

D

Which of the following expressions is the correct equilibrium-constant expression for the reaction below? (NH4)2Se (s) <--> 2NH3 (g) + H2Se (g) A) [NH3][H2Se] / (NH4)2Se B) (NH4)2Se / [NH3]^3[H2Se] C) 1 / [(NH4)2Se] D) [NH3]^2[H2Se] E) [NH3]^2[H2Se] / [(NH4)2Se]

D

Which of the following ions will act as a weak base in water? A) OH- B) Cl- C) NO3- D) ClO- E) None of the above will act as a weak base in water.

D

24) A 25.0 mL sample of a solution of a monoprotic acid is titrated with a 0.115 M NaOH solution. The titration curve above was obtained. The concentration of the monoprotic acid is about __________ mol/L. A) 25.0 B) 0.0600 C) 0.240 D) 0.120 E) 0.100

D) 0.120

The mole fraction of He in a gaseous solution prepared from 3.0 g of He, 6.5 g of Ar, and 10.0 g of Ne is __________. A) 0.20 B) 0.75 C) 0.86 D) 0.53 E) 0.66

D) 0.53

Calculate the molality of a 25.4% (by mass) aqueous solution of phosphoric acid (H₃PO4). A) 2.59 m B) 4.45 m C) 25.4 m D) 3.47 m E) The density of the solution is needed to solve the problem.

D) 3.47 m

If the partial pressure of oxygen in the air a diver breathes is too great: A) hyperventilation results B) the urge to breathe is increased and excessive CO₂ is removed from the body C) respiratory tissue is damaged by oxidation D) the urge to breathe is reduced and not enough CO₂ is removed from the body E) No problems result from this situation.

D) the urge to breathe is reduced and not enough CO₂ is removed from the body

2. A sample of potassium chlorate (15.0 g) is dissolved in 200 g of water at 70 °C with precautions taken to avoid evaporation of any water. The solution is cooled to 30.0 °C and no precipitate is observed. This solution is __________. A) Hydrated B) Miscible C) Saturated D) Unsaturated E) Supersaturated

D. Unsaturated

CaCO3 (s) CaO (s) + CO2 (g) Le Chatelier's principle predicts that __________ will result in an increase in the number of moles of CO2. A. decreasing the temperature B. removing some of the CaCO3 (s) C. increasing the pressure D. increasing the temperature E. adding more CaCO3 (s)

D. increasing the temperature

The relationship between the change in Gibbs free energy and the emf of an electrochemical cell is given by

Delta G=-nFE

A Br0nsted-Lowry acid is defined as a substance that __________. A) increases Ka when placed in B) decreases [H+] when placed in H2O C) increases [OH-] when placed in H2O D) acts as a proton acceptor E) acts as a proton donor

E

Catalysts in living organisms is achieved by =

Enzymes (large protein molecules that usually catalyze a very specific r x n.

Rate is proportional to the concentration of a single reactant raised to to the 1st power=

First order reaction: Rate = k[A] in such cases the integrated form of the rate law is: ln[A]t = -kt + ln[A]o [A]t = concentration of reactant A at a time, t; k = rate constant; [A]o = initial concentration of A.

4. The ________________________ is related to the probability that a collision will lead to a reaction.

Frequency Factor

conjugate acid

H+ added to base

Oxidation Numbers HNO₂

H= +1 N= 3+ O= 2-

15) Of the following, __________ is a weak acid. A) HF B) HCl C) HBr D) HNO3 E) HCIO4

HF

Of the acids in the table below, _____ is the strongest acid. Acid Ka HOAc 1.8 x 10^-5 HCHO2 1.8 x 10^-4 HClO 3.0 x 10^-8 HF 6.8 x 10^-4

HF

Le Chatelier's Principle

If a stress is applied to a system in equilibrium then the system readjusts itself so as to undo the affect of that stress

k[A][B]²

If the rate law for the reaction 2A + 3B → products is first order in A and second order in B, then the rate law is rate = ________. A) k[A][B] B) k[A]²[B]³ C) k[A][B]² D) k[A]²[B] E) k[A]²[B]²

k[A]²[B]

If the rate law for the reaction 2A + 3B → products is second order in A and first order in B, then the rate law is rate = ________. A) k[A][B] B) k[A]²[B]³ C) k[A][B]² D) k[A]²[B] E) k[A]²[B]²

Now Calculate molality, m (mol solute/kg solvent)

In our 1 L we had 1211 g total of which 417.8 g were H3PO4 How many grams of water do we have? g water = (total g) - (g H3PO4 ) = 1211-417.8 = 793.2 g We need kg of solvent 793.2 g = 0.7932 kg Calculate m: m = 4.28 mol /0.7932 kg = 5.37 m

relationship between K(b) and K(c) formula

K(a) x K(b) = K(w)=1.0 x 10⁻¹⁴ pK(a) + Pk(b) = pK(w) = 14.00

The following reaction carried out at 298 K with the initial concentration of NO₂ being 0.70 M.At equilibrium the NO₂ concentration was found to be 0.28 M. Calculate the Keq for this reaction. 2NO₂ (G) ↔ 2NO (g) + O₂ (g)

Keq= 0.47

What is the predominant intermolecular force in CBr4?

London-dispersion forces

Catalysts affect speed equilibrium is reached but does not affect →

Magnitude of K

amphoteric

Metal oxides and hydroxides that are relatively insoluble in neutral water, but are soluble in both strongly acidic and strongly basic solutions are said to be __________.

The number of molecules that particupate as reactants defines the ___________ of the reaction.

Molecularity

The pH of a 0.55 M aqueous solution of hypobromous acid, HBrO, at 25.0 °C is 4.48. What is the value of Ka for HBrO?

Neptune 2.0

Will decrease in volume favor the decomposition of NH4HS?

No

0.821 M HF and 0.909 M NaF

Of the following solutions, which has the greatest buffering capacity?

Br2

Of the following, __________ has the highest boiling point.

PV=nRT

P=nRT/V ; V=nRT/P ; n=PV/RT ; T=PV/nR P=nRT/V = (n/V)(RT) PV/T=nR=constant ; P₁V₁/T₁=P₂V₂/T₂ ; V₂=V₁ x P₁/P₂ x T₂/T₁ ;T₂=T₁x P₂/P₁xV₂/V₁ ; n/v=P/RT ; d=nM/V=PM/RT ; M=dRT/P ; V=m/d

Of the substances below, __________ will decrease the solubility of Pb(OH)2 in a saturated solution. a. NaNO3 b. H2O2 c. HNO3 d. Pb(NO3)2 e. NaCl

Pb(NO3)2

The lowering of vapor pressure is expressed by ----

Raoult's Law An ideal solution obeys Raoult's Law.

The amount of solute needed to form a saturated soln. at any particular temperature is the -----

Solubility of that solute at that temperature.

1. Homogenous mixture of 2 or more subsatnces

Solution

13.3

The Keq for the equilibrium below is 7.52 × 10-2 at 480.0 °C. 2Cl2 (g) + 2H2O (g) 4HCl (g) + O2 (g) What is the value of Keq at this temperature for the following reaction? 4HCl (g) + O2 (g) 2Cl2 (g) + 2H2O (g)

C2H5NH2

The addition of hydrochloric acid and ________ to water produces a buffer solution. A) HC6H5O B) NaOH C) NaCl D) C2H5NH2 E) none of the above

1

The data in the table below were obtained for the reaction: (see photo) 2 ClO₂ (aq) + 2 OH⁻ (aq) → ClO₃⁻ (aq) + ClO₂⁻ (aq) + H₂O (1) A) 0 B) 1 C) 2 D) 3 E) 4

surface tension

The property responsible for the "beading up" of water is

The reaction is first order overall.

The rate law for a reaction is rate = k[A][B] Which one of the following statements is false? A) The reaction is first order overall. B) The reaction is first order in A. C) The reaction is first order in [B]. D) k is the reaction rate constant E) If [A] is doubled, the reaction rate will increase by a factor of 2.

At equilibrium

The rates of the forward and reverse reactions are equal

Condensed

Together, liquids and solids constitute __________ phases of matter.

True/ False The sum of the oxidation numbers of all atoms in a neutral compound is 0.

True

True

True or False Adding a nonvolatile solute to a solution decreases the vapor pressure of the solution.

If there is less solute present than is need to saturate the soln. the soln is :----------

Unsaturated

1.3 × 10-5

What is the molar solubility of silver chloride ( AgCl ) in water? The solubility-product constant for AgCl is 1.8 × 10-10 at 25 °C.

hydration

When solutions of strong electrolytes in water are formed, the ions are surrounded by water molecules. These interactions are described as a case of __________.

acetic acid or hydrochloric acid

Which of the following could be added to a solution of sodium acetate to produce a buffer? A) acetic acid only B) acetic acid or hydrochloric acid C) hydrochloric acid only D) potassium acetate only E) sodium chloride or potassium acetate

CH4

Which of the following has dispersion forces as its only intermolecular force?

Which below best describe(s) the behavior of an amphoteric hydroxide in water? a. With conc. aq. NaOH, its suspension dissolves. b. With conc. aq. HCl, its suspension dissolves. c. With conc. aq. NaOH, its clear solution forms a precipitate. d. With conc. aq. HCl, its clear solution forms a precipitate. e. With both conc. aq. NaOH and conc. aq. HCl, its suspension dissolves.

With both conc. aq. NaOH and conc. aq. HCl, its suspension dissolves.

Which of the following is the definition of chirality? a. The non-superposability of an object on its mirror image b. The superposability of an object on its mirror image c. A molecule that has a carbon atom with four different substituents d. A molecule with a mirror image

a

Which of the following is the strongest base? a. NaOH b. NaCO3 c. H2O d. CH3OH

a

What is used to determine when a solution has reached its equivalence point?

a pH meter or dye indicators

Bronstead-Lowry Base

a proton acceptor (gains an H+ during a reaction)

Bronstead-Lowry Acid

a proton donor (loses an H+ during a reaction)

homogenous reaction

a reaction in which all of the reactants and products are in the same phase (gas or liquid)

heterogenous reaction

a reaction where the reactants are in different phases. these reactions are limited by the area of contact between the molecules. so for solids, they will proceed QUICKER if the surface area of solid is increased ex. a fine powder medication will dissolve quicker than a tablet medication

when acids react with metals, they produce _____ gas. a. hydrogen b. nitrogen c. sulfur d. oxygen

a. hydrogen

Which statements about viscosity are true? (i) Viscosity increases as temperature decreases. (ii) Viscosity increases as molecular weight increases. (iii) Viscosity increases as intermolecular forces increase.

all

Large intermolecular forces in a substance are manifested by __________.

all of these

The rate of a reaction depends on __________.

all of these

Which one of the following is a Bronsted-Lowry acid?

all of these

heterogeneous catalysts

are catalyst that are present in a different state as the reactants in a reaction mixture

homogenous catalysts

are catalyst that is present in the same phase (state) as the reactants in a reaction mixture

buffered solutions

are solutions that contain a weak conjugate aid base pair. They resist drastic changes in pH when small amounts of strong acid or strong base are added to them. (human blood is an example, it maintains the blood pH at about 7.4)

the speed of an event is defined

as the change that occurs in a given time interval, which means that whenever we talk about speed, we necessarily bring in the notion of time.

How many stereoisomers of 3-chloro-2-methylbutane, (CH3)2CHCHClCH3, exist? a. 1 b. 2 c. 3 d. 4

b

In the reaction 2Cs + CL₂ → 2CsCl, CL₂ is a.the reducing agent b. the oxidizing agent c. oxidized d. the electron donor

b. the oxidizing agent

Strong reducing agents are substances that easily ___ electrons a. gain b. give up c. share d. bond

b.give up

An aqueous solution contains 0.10 M NaOH. The solution is ____.

basic

Substances with acidic cations are more soluble in ______ solutions.

basic

if [H30+] < [OH-] then the solution is

basic

pH > 7

basic

the average rate of disappearance or B formula

change in concentration of B/ change in time ∆B/∆t

instantanous rate formula

change in molarity/change in time ∆m/∆t

Which one of the following will change the value of equilibrium constant?

changing temperature

The rate of a reaction depends on

collision orientation, collision energy,collision frequency

Whenever a weak electrolyte and a strong electrolyte containing a common ion are together in a solution, the weak electrolyte ionizes less than it would if it were alone in a solution.

common-ion effect

Hydroxides of Al3+, Cr3+, Zn2+, and Sn2+ generally form _____ ____ with four ____ _____ attached to the metal.

complex ions; hydroxide ligands

On the phase diagram, the point corresponding to the critical temperature and pressure is _____.

critical

How many isomers (constitutional and stereoisomers) exist for dimethylcyclobutane? a. 3 b. 4 c. 5 d. 6

d

How many isomers (constitutional and stereoisomers) exist for dimethylcyclohexane? a. 3 b. 5 c. 6 d. 9

d

How many stereoisomers of 3-bromo-2-butanol, CH3CH(OH)CHBrCH3, exist? a. 1 b. 2 c. 3 d. 4

d

How many stereoisomers of 4-bromo-2-pentanol, CH3CH(OH)CH2CHBrCH3, exist? a. 1 b. 2 c. 3 d. 4

d

When potassium chloride, KCl, dissolves in water, it dissociates (breaks apart) into: a. H+ ions b. K+ and Cl+ ions c. OH- ions d. K+ and Cl- ions

d (K+ and Cl- ions)

Which atom(s) would gain electrons if lithium (alkali metal) and chlorine (halogen) were to combine chemically? a. lithium b. neither lithium nor chlorine c. both lithium and chlorine d. chlorine

d (chlorine)

What do the dotted lines indicate in a diagram of a water molecule bonding? a. ionic bonds b. covalent bonds c. double bonds d. hydrogen bonds

d (hydrogen bonds)

Which of the following states that if a change in conditions is imposed on a system at equilibrium, the equilibrium position will shift in the direction that tends to reduce that change in conditions. a. law of chemical equilibrium b. law of mass action c. law of balancing d. Le Chatielier's Principle

d. Le Chatielier's Principle

half life

decrease of 50% in a time period

In general, the solubility of a slightly soluble salt is __________ by the presence of a second solute that furnishes a common ion.

decreased

At constant temperature, reducing the volume of a gaseous equilibrium mixture causes the reaction to shift in the direction that _________ the number of moles of gas in the system

decreases

Consider the following reaction at equilibrium: C(s)+H2O(g)= CO(g) +H2(g) Which of the following conditions will increase the partial pressure of CO?

decreasing the pressure in the reaction vessel

Which one of the following processes produces a decrease of the entropy of the system? A) dissolving sodium chloride in water B) sublimation of naphthalene C) dissolving oxygen in water D) boiling of alcohol E) explosion of nitroglycerine D) dissolving oxygen in water

dissolving oxygen in water

Which of the following reactions does not involve oxidation-reduction a. CH₄ + 3O₂ → 2H₂O + CO₂ b. Zn + 2HCl → ZnCl2 + H₂ c. 2Na + 2H₂O → 2NaOH + H₂ d. MnO₂ + 4HCl → Cl₂ + 2H₂O + MnCl₂ e. all are oxidation-reduction reactions

e. all are oxidation-reduction reactions

Oxidation cannot occur without ___ a. acid b.oxygen c. water d. air e. reduction

e. reduction

The thermodynamic quantity that expresses the degree of disorder in a system is __________.

entropy

the rate of disappearance A ...... the disappearance of substance B

equals

Catalysts raise the activation energy

false

In an exothermic equilibrium reaction, increasing the reaction temperature favors the ________

formation of reactants

In general, as temperature goes down, reaction rate __________.

goes down regardless of whether the reaction is exothermic or endothermic

Solubility is the amount (_____) of substance that dissolves to form a (________) solution.

grams; saturated

A catalyst that is present in a different phase as the reacting molecules is called a ________ catalyst

heterogeneous

Heat + NH₄Cl (s) ↔ NH₃ (g) + HCl (g) is the equilibrium reaction homogeneous or heterogeneous ?

heterogeneous

Catalyst that is in the same phase as reactants =

homogenous catalyst

the solubility product constant indicates

how soluble the solid is in water

the exponents in the rate law indicate

how the rate is affected by each reactant concentration

Compounds composed of a salt and water combined in definite proportions are known as ____.

hydrates

When solutions of strong electrolytes in water are formed, the ions are surrounded by water molecules. These interactions are described as a case of __________.

hydration

Binary acids are named with the prefix ______ and end with -_____ acid

hydro- , -ic acid (hydro-stem of nonmetal-ic acid)

the speed of a chemical reaction (its reaction time) is the change

in the concentration of reactants or products per unit of time

What is the typical effect of the addition of an interstitial element on the properties of a metal?

increase in hardness and strength, decrease in ductility

The effect of a catalyst on equilibrium is to ________.

increase the rate at which equilibrium is achieved without changing the composition of the equilibrium mixture

equivalence point..... as K(a) decreases

increases

The solubilities of most solid solutes in water ------- as the temperature of the soln. --------

increases, increases

initial rate

instantaneous rate at t=0

buffer capacity

is the amount of acid or base the buffer can neutralize before the pH begins to change to an appreciable degree. it depends on the amount of acid and base used to prepare the buffer. The more moles we have the more buffering capacity it has.

Which of the following is not classified as a nanomaterial?

isoprene

The relationship between the concentrations of reactants and products of a system at equilibrium is given by the __________

law of mass action

Decreasing T in an endothermic reaction causes the equilibrium to shift _____.

left

Absorption of a reactant at specific sites on the surface makes bond breaking easier thus =

lowering the activation energy

What are the principal organs that regulate the pH of the carbonic acid-bicarbonate buffer system in the blood?

lungs, kidneys

resonance of conjugate bases of carboxylic acids stabilizes the base and

makes the conjugate acid more acidic

The solubility product is the _____ ___________ of ions raised to their stoichiometric powers.

molar concentration

HZ is a weak acid. An aqueous solution of HZ is prepared by dissolving 0.020 mol of HZ in sufficient water to yield 1.0 L of solution. The pH of the solution was 4.93 at 25.0 °C. The Ka of HZ is __________.

neptune 6.9

if [OH-] = 1.0 x 10^-7 M then the solution is

neutral

H₂ (g) + I₂(g) ↔ 2HI 9G) + heat if pressure is increased, will the reaction shift to the right, left, or no change?

no change

Which one of the following reactions is a redox reaction?

none of this is a redox reaction.

Which of the following is not a natural polymer?

nylon

The effect of ____ on solubility is dramatic.

pH

buffers a resistant to ______ changes

pH

pKw =

pH + pOH = 14.00 at 25 Celsius

for an acidic solution pH _______ and pOH __________ at 25 degree celsius

pH <7 and pOH > 7 at 25 degree celsius

for a neutral solution

pH = pOH = 7 at 25 degree celsius

weak electrolyte

partially ionizes in water

The phrase "like dissolves like" refers to the face that ____.

polar solvents dissolve polar solutes and non polar solvents dissolve non polar solutes

When a _____ acid is titrated with a base, there is an equivalence point for each dissociation.

polyprotic

If a substance is removed from a system, the system reacts to ______ of a substance.

produce more

Arrhenius acid

produces H+ (protons) ions in water

A reaction was found to be zero order in A. Increasing the concentration of A by a factor of 3 will cause the reaction rate to __________.

remain constant

conjugate base

remove H+ from acid

Decreasing T in an exothermic reaction causes the equilibrium to shift _____.

right

Which of the following could be added to a solution of acetic acid to prepare a buffer?

sodium acetate or sodium hydroxide

Which of the following could be added to a solution of acetic acid to prepare a buffer? a. sodium acetate only b. sodium acetate or sodium hydroxide c. nitric acid only d. hydrofluoric acid or nitric acid e. sodium hydroxide only

sodium acetate or sodium hydroxide

if k(b) is larger than k(a)

solution will be basic

what is a strong base?

something that completely associates in a solution

what is a strong acid?

something that completely dissociates in a solution

What is a weak acid?

something that does not completely dissociate in a solution

Catalyst

speeds up a chemical reaction

The pH of a 0.10 M solution of a weak base is 9.82. What is the Kb for this base?

spider 4.4

reaction mechanism

step-by-step molecular level view or the pathway from reactants to products

The equilibrium constant expression depends on the ____ of the reaction.

stoichiometry

The equilibrium-constant expression depends on the ________ of the reaction.

stoichiometry

The equilibrium-constant expression depends on the __________ of the reaction.

stoichiometry

Elementary reactions involving the simultaneous collision of three molecules are __________.

termolecular

In a solution, when the concentrations of a weak acid and its conjugate base are equal,

the -log of the [H+] and the -log of the Ka are equal

it is typical for rates to decrease as a reaction proceeds because

the concentration of reactants decreases

how does physical state of the reactants affect reaction rates?

the easier it is for the molecules to collide(react) the quicker the reaction will happen. heterogenous reactions are limited by the area conrtact of the molecules.

The formation of a condensation polymer generally involves __________.

the elimination of a small molecule

One difference between first- and second-order reactions is that __________.

the half-life of a first-order reaction does not depend on [A]0; the half-life of a second-order reaction does depend on [A]0

Colligative properties of solutions include all of the following except __________.

the increase of reaction rates with increase in temperature

rate constant

the magnitude of the rate constant (k) changes with temperature and therefore determines how temp affects rate.

Density

the mass of a substance divided by its volume (D=M/V)

solubility is not the same as K(sp) solubility is expressed as

the mass of solute dissolved in 1 L or solution .

in oxyacids (which are OH attached to another atom)

the more electronegative Y (atom) is the more acidic the acid

On a phase diagram, the critical pressure is __________.

the pressure required to liquefy a gas at its critical temperature

the solubility product K(sp) of a compound equals

the product of the concentration of the ions involved in the equilibrium, each raised to the power of its coefficient in the equilibrium equation.

pH range

the range of pH values over which a buffer system works effectively

instantaneous rate

the rate at a particular instant during the reaction -it is determined from the slope of the cure at a particular point in time

At equilibrium, ____.

the rates of the forward and reverse reactions are equal

reaction rate

the speed at which a chemical reaction occurs. the change in concentration of reactants or products over a unit of time. usually M/s (molarity/second)

chemical kinetics

the study of reaction rates

If Q == K then

the system is at equilibrium

If Q != K then

the system is not at equilibrium

On a phase diagram, the critical temperature is __________.

the temperature above which a gas cannot be liquefied

amphoteric metal oxides and hydroxides are soluble in a strong acid or base because?

they can act as a strong acid or base

At equilibrium the forward rate of formation of the products equals the reverse rate for formation of the reactants.

true

If the value for the equilibrium constant is much greater than 1, then the equilibrium mixture contains mostly products

true

units of rate constant formula

units of rate constant= units of rate / units of concentration ² (M/s) / M²

Consider a pure crystalline solid that is heated from absolute zero to a temperature above the boiling point of the liquid. Which of the following processes produces the greatest increase in the entropy of the substance? A) melting the solid B) heating the liquid C) heating the gas D) heating the solid E) vaporizing the liquid

vaporizing the liquid

the stronger the acid the ________ the conjugate base is

weaker

the stronger the base the ______ the conjugate acid is

weaker

The reaction A --> B is first order in [A]. Consider the following data. Time (s) [A] (M) 0.0 1.60 10.0 0.40 20.0 0.10 The rate constant for this reaction is __________ s^-1.

0.14

In which of the following aqueous solutions you expect AgBr to have the lowest solubility? a. pure water b. 0.20 M NaBr c. 0.10 M AgNO3 d. 0.15 M KBr e. 0.10 M LiBr

0.20 M NaBr

The value of Delta G° for a reaction conducted at 25 °C is 3.05 kJ/mol. The equilibrium constant for a reaction is ____ at this temperature?

0.292

At elevated temperatures, molecular hydrogen and molecular bromine react to partially form hydrogen bromide: H₂ (g) + Br₂ (g) ↔ 2HBr (g) a mixture of 0.682 mol of H₂ and 0.440 mol of Br₂ is combined in a reaction vessel with a volume of 2.00 L. At equilibrium at 700 K , there are 0.566 mol of H₂ present. How many moles of Br₂ are present in the reaction vessel at equilibrium?

0.324 moles of Br₂

Of the following solutions, which has the greatest buffering capacity? a. 0.543 M NH3 and 0.555 M NH4Cl b. 0.087 M NH3 and 0.088 M NH4Cl c. 0.234 M NH3 and 0.100 M NH4Cl d. 0.100 M NH3 and 0.455 M NH4Cl e. They are all buffer solutions and would all have the same capacity.

0.543 M NH3 and 0.555 M NH4Cl

Of the following solutions, which has the greatest buffering capacity?

0.543M NH3 and 0.555 M NH4Cl

A solution is prepared by dissolving 23.7 g of CaCl2 in 375 g of water. The density of the resulting solution is 1.05 g/mL. The concentration of CaCl2 in this solution is __________ molar.

0.56

A solution is prepared by dissolving 23.7 g of CaCl2 in 375 g of water. The density of the resulting solution is 1.05 g/mL. The concentration of CaCl2 in this solution is __________ molal.

0.569

In which aqueous system is PbI2 least soluble? a. H2O b. 0.5MHI c. 0.2MHI d. 1.0 M HNO3 e. 0.8MKI

0.8MKI

A category __________ plastic container will generally be the most easily recycled.

1

The data in the table below were obtained for the reaction: 2 ClO2 (aq) + 2 OH^- (aq) = ClO3^- (aq) + ClO2^- (aq) + H2O (l) What is the order of the reaction with respect to OH-? 1 0.060 0.030 0.0248 2 0.020 0.030 0.00276 3 0.020 0.090 0.00828

1

CsCl crystallizes in a unit cell that contains the Cs+ ion at the center of a cube that has a Cl- at each corner. Each unit cell contains __________ Cs+ ions and __________ Cl-, ions, respectively.

1 and 1

Chemists generally refer to solvents as hydrophilic (water-loving) or hydrophobic (water-hating) based on their ability to dissolve in water. The following factors favor hydrophilicity. They are listed in order of importance.

1) The presence of ions. 2) The presence of a dipole moment. 3) The presence of London dispersion forces.

what are the four factors that affect reation rates?

1) physical state of the reactants 2) reactant concentration 3) reaction temperature 4) presence of a catalyst

The molar concentration of hydroxide ion in pure water at 25 °C is ____.

1.0 x 10^-7

The molar concentration of hydronium ion in pure water at 25°C is __________.

1.0 × 10^-7

A solution is prepared by dissolving 23.7 g of CaCl2 in 375 g of water. The density of the resulting solution is 1.05 g/mL .The concentration of Cl- in this solution is __________ M.

1.12

The concentration of fluoride ions in a saturated solution of barium fluoride is __________ M. The solubility product constant of BaF2 is 1.7\:x\:10^{-6}.

1.5 x 10-2

The concentration of fluoride ions in a saturated solution of barium fluoride is ________ M. The solubility product constant of BaF2 is 1.7 ⋅ 10^-6.

1.5 ⋅ 10-2 Ksp = 1.7 ⋅ 10^-6 = (x)(2x)^2 = 4x^3 x = 0.0075 [F-] = 2 x 0.0075 = 0.0015

A flask is charged with 0.124 mol of A and allowed to react to form B according the the reaction A(g) → B(g). The following data are obtained for [A] as the reaction proceeds: Time(s) 0.00 10.00 20.0 30.0 40.0 Moles of A 0.124 0.110 0.088 0.073 0.054 The average rate of disappearance between 20s and 40s is ________mol/s

1.7 x 10⁻³

Calculate the maximum concentration (in M) of silver ions (Ag+) in a solution that contains 0.025 M of CO_3\:^{2-}. The Ksp of Ag2CO3 is 8.1\:x\:10^{-12}.

1.8 x 10-5

The pH of a 0.60 M aqueous solution of formic acid, HCHO2, at 25.0 °C is 1.98. What is the value of Ka for formic acid?

1.8 x 10^-4

A reaction vessel is charged with hydrogen iodide, which partially decomposes to molecular hydrogen and iodine: 2 HI (g) = H2 (g) + I2 (g) When the system comes to equilibrium at 425 °C, P_HI = 0.708 atm, and P_H2 = P_I2 = 0.0960 atm. The value of Kp at this temperature is ____.

1.84 x 10^-2

A reaction vessel is charged with hydrogen iodide, which partially decomposes to molecular hydrogen and oidine: 2HI (g) ↔ H₂ (g) + I₂ (g) When the system comes to equilibrium at 425 °C, Phi = 0.708 atm, and Ph₂ = 0.0960 atm. The value of Kp at this temperature is ________.

1.84 x 10⁻²

What is the molar solubility of magnesium carbonate ( MgCO3) in water? The solubility-product constant for MgCO3 is 3.5 × 10-8 at 25 °C.

1.9 × 10-4

Given the following reaction at equilibrium, if Kc = 1.90 x 10^19 at 25.0 °C, Kp = ____. H2 (g) + Br2 (g) = 2 HBr (g)

1.90 x 10^19

the effect of cations and anions

1.an anion that is the conjugate base of a strong acid will not affect the pH 2. an anion that is the conjugate base of a weak acid will increase the pH 3.a cation that is the conjugate acid of a weak base will decrease the pH 4.cations of strong Arrhenius bases will not affect pH 5.other metal ions will cause decrease in pH 6.when solution contains both weak acid and weak base the effect on pH depends on the K(a) and K(b) values

4 factors that affect reaction rates

1.physical state of the reactants 2.reactant concentrations 3.reaction temperature 4.the presence of a catalyst

What fraction of the volume of each corner atom is actually within the volume of a face-centered cubic unit cell?

1/8

The equilibrium constant for reaction 1 is K. The equilibrium constant for reaction 2 is ____. 1. SO2 (g) + 1/2 O2 (g) = SO3 (g) 2. 2 SO3 (g) = 2 SO2 (g) + O2 (g)

1/K^2

The overall order of a reaction is 1. The units of the rate constant for the reaction are _________.

1/s

An aqueous solution contains 0.100 M NaOH at 25.0 °C. The pH of the solution is __________.

13.00

Given the following reaction: CO (g) +2H₂ (g) ↔ CH₃OH (g) In an experiment, 0.42 mol of CO and 0.42 mol of H₂ were placed in a 1.00-L reaction vessel. At equilibrium, there were 0.29 mol of CO remaining. Keq at the temperature of the experiment is _______.

17.5

In what year was Fritz Haber awarded the Nobel Prize in chemistry for his development of a process for synthesizing ammonia directly from nitrogen and hydrogen?

1918

The data in the table below were obtained for the reaction: 2 ClO2 (aq) + 2 OH- (aq) = ClO3^- (aq) + ClO2^- (aq) + H2O (l) What is the order of the reaction with respect to ClO2? 1 0.060 0.030 0.0248 2 0.020 0.030 0.00276 3 0.020 0.090 0.00828

2

What is the coefficient of Fe^(3+) when the following equation is balanced? CN^(-) + Fe^(3+) ----> CNO^(-) + Fe^(2+) (Basic solution)

2

What is the coefficient of the permanganate ion when the following equation is balanced? MnO4^- + Br + Mn^(2+) + Br2 (acidic solution)

2

Of the following equilibria, only ________ will shift to the left in response to a decrease in volume

2 SO3 (g) --> 2 SO2 (g) + O2 (g)

A flask is charged with 0.124 mol of A and allowed to react to form B according the the reaction A(g) → B(g). The following data are obtained for [A] as the reaction proceeds: Time(s) 0.00 10.00 20.0 30.0 40.0 Moles of A 0.124 0.110 0.088 0.073 0.054 The average rate of disappearance of A between 10s and 20s is ___________mol/s.

2.2 x 10⁻³

A compound decomposes by a first-order process. If 17.0% of the compound decomposes in 60.0 minutes, the half-life of the compound is __________.

223 minutes

The data in the table below were obtained for the reaction: 2 ClO2 (aq) + 2 OH^- (aq) = ClO3^- (aq) + ClO2^- (aq) + H2O (l) What is the magnitude of the rate constant for the reaction? 1 0.060 0.030 0.0248 2 0.020 0.030 0.00276 3 0.020 0.090 0.00828

230

Write the chemical equation of the following gaseous homogeneous equilibrium expressions [SO₂]² [O₂] / [SO₃]²

2SO₃ (g) ↔ 2SO₂ (g) + 0₂ (g)

Overall reaction order is 2.

2nd order reaction: if 2nd order rate law depends on concentration of only one reactant, then rate = k[A]^2, and time dependence of [A] is given by integrated rate law: 1/[A]t = 1/[A]o + kt. (in this case a graph of 1/[A]t versus time yields a straight line.

The data in the table below were obtained for the reaction: What is the overall order of the reaction? 1 0.060 0.030 0.0248 2 0.020 0.030 0.00276 3 0.020 0.090 0.00828

3

Calculate the molality of a 25.4% (by mass) aqueous solution of phosphoric acid (H3PO4).

3.47 m

The Keq for the equilibrium below is 7.52 × 10-2 at 480.0 °C. What is the value of Keq at this temperature for the following reaction?

3.65

At elevated temperatures, methylisonitrile (CH₃NC) isomerizes to acetonitrile (CH₃CN): CH₃NC (g) → CH₃CN (g) At the start of the experiment , there are 0.200 mol of reactant and 0 mol of product in the reaction vessel. After 25 min of reaction, 0.108 mol of reactant remain. The average rate of decomposition of CH₃NC in this 25 min period is _______.

3.7 x 10⁻³

Calculate the pH of a solution that is 0.290 M in sodium formate (NaHCO2) and 0.210 M in formic acid (HCO2H). The Ka of formic acid is 1.77 ⋅ 10^-4.

3.885 Ka = [HA][H+]/[A-] pH = -log[H+]

What is the pH of a 0.1 molar solution of AlCl3

3.96

Consider the reaction: NH3 (g) + HCl (g) --> NH4Cl (s) Given the following table of thermodynamic data, Substance Delta Hf (kJ/mol) S° (J/mol*K) NH3 (g) -46.19 192.5 HCl (g) -92.30 186.69 NH4Cl (s) -314.4 94.6 determine the temperature (in °C) above which the reaction is nonspontaneous.

345.0

Calculate the pOH of a solution at 25.0 °C that contains 1.94 × 10-10 M hydronium ions.

4.29 (orange igloo)

The solubility of manganese (II) hydroxide (Mn(OH)2) is 2.2x10^{-5}.2.2x10−5. What is the Ksp of Mn(OH)2?

4.3 x 10-14

The Ka of hypochlorous acid (HClO) is 3.00 × 10-8 at 25.0 °C. Calculate the pH of a 0.0385 M hypochlorous acid solution.

4.47 (green giraffe)

Calculate the pH of a solution prepared by dissolving 0.150 mol of benzoic acid and 0.300 mol of sodium benzoate in water sufficient to yield 1.00 L of solution. The Ka of benzoic acid is 6.30x10^{-5}.

4.502

You need 12.0 g of K2CrO4. You have a solution labeled 5.00 % K2CrO4 by mass. How much of this solution should you weigh out?

5 % = 5 g /100 g of solution. So you just need to set up a proportion. 5 g / 100 g = 12.0 g/ X X = 240. g Soln.

The reaction A --> B is first order in [A]. Consider the following data. Time (s) [A] (M) 0.0 1.60 10.0 0.40 20.0 0.10 The half-life of this reaction is __________ s.

5.0

12 karat gold contains __________% gold.

5.0 x 10^1

What is the pH of an aqueous solution at 25 °C that contains 3.98 x 10^-9 M hydroxide ion?

5.60

39. As the concentration of a solute in a solution increases, the freezing point of the solution _ and the vapor pressure of the solution _

(C) decreases, decreases

29. Pressure has an appreciable effect on the solubility of ________ in liquids.

(C) gases

35. Of the concentration units below, only ________ uses kg of solvent in its calculation

(C) molality

36. A solution contains 11% by mass of sodium chloride. This means that _

(D) 100 g of the solution contains 11 g of sodium chloride

26. The concentration of CO2 in a soft drink bottled with a partial pressure of CO2 of 4.0 atm over the liquid at 25 °C is 1.2 ⋅ 10-1 M. The Henry's law (Sg = k Pg) constant for CO2 at this temperature is:

(D) 3.0 x 10-2 mol / L-atm

22. Which of the following substances is more likely to dissolve in water?

(D) HOCH2CH2OH

30. Which of the following statements is false?

(D) The weaker the attraction between the solute and solvent molecules, the greater the solubility

21. Compounds composed of a salt and water combined in definite proportions are known as:

(D) hydrates

38. A 0.100 m solution of which one of the following solutes will have the highest vapor pressure?

(D) sucrose

32. If the partial pressure of oxygen in the air a diver breathes is too great, _

(D) the urge to breathe is reduced and not enough CO2 is removed from the body

31. Which of the following choices has the compounds correctly arranged in order of increasing solubility in water? (least soluble to most soluble)

(E) CCl4 < CHCl3 < NaNO3

33. Calculate the molarity of a 17.5% (by mass) aqueous solution of nitric acid.

(E) The density of the solution is needed to solve the problem

A reaction that is not spontaneous at low temperature can become spontaneous at high temperature if Delta H is __________ and Delta S is __________.

+,+

A flask is charged with 0.124 mol of A and allowed to react to form B according the the reaction A(g) → B(g). The following data are obtained for [A] as the reaction proceeds: Time(s) 0.00 10.00 20.0 30.0 40.0 Moles of A 0.124 0.110 0.088 0.073 0.054 The average rate of appearance between 20s and 30s is ________mol/s

+1.5 x 10⁻³

What is the pH of an aqueous solution at 25.0 °C in which [OH- ] is 0.00250 M?

+11.4

Consider the following reaction: A→2C The average rate of appearance of C is given by delta C/delta t. Comparing the rate of appearance of C and the rate of disappearance of A we get delta C/delta t = ________x (-delta A/delta t)

+2

The Ka of acetic acid (HC2H3O2) is 1.8 x 10^-5. What is the pH at 25.0 °C of an aqueous solution that is 0.100 M in acetic acid?

+2.87

Consider the following reaction 3A→2B The average rate of appearance of B is given by delta B/delta t. Comparing the rate of appearance of B and the rate of disappearance of A, we get delta B/delta t = ___________ x(-delta A/delta t)

+2/3

pH =

- log [H3O+] and [H3O+]= 10-pH

A 25.0 mL sample of a solution of a monoprotic acid is titrated with a 0.115 M NaOH solution. The titration curve above was obtained. The concentration of the monoprotic acid is about ________ mol/L.

0.120

Hydrophobic colloids: A) can be stabilized by coagulation B) will separate into two phases if they are stabilized C) are those that contain water D) are those that do not contain water E) can be stabilized by adsorption of ions

E) can be stabilized by adsorption of ions

17) The primary buffer system that controls the pH of the blood is the __________ buffer system. A) carbon dioxide, carbonate B) carbonate, bicarbonate C) carbonic acid, carbon dioxide D) carbonate, carbonic acid E) carbonic acid, bicarbonate

E) carbonic acid, bicarbonate

19) Human blood is __________. A) neutral B) very basic C) slightly acidic D) very acidic E) slightly basic

E) slightly basic

The magnitudes of Kf and of Kb depend on the identity of the __________. A) solute B) solvent and on temperature C) solute and solvent D) solution E) solvent

E) solvent

A Bronsted-Lowry base is defined as a substance that _____. A. Increases [H+] when placed in H₂O B. Increases [OH-] when placed in H₂O C. Acts as a proton donor D. Decreases [H+] when placed in H₂O E. Acts as a proton acceptor

E. Acts as a proton acceptor

A substance that is capable of acting as both an acid and a as a base is: A. Saturated B. Miscible C. Conjugated D. Autosomal E. Amphoteric

E. Amphoteric

An aqueous solution of ________ will produce a basic solution. A. NaCl B. NaHSO₄ C. KBr D. NH₄ClO₄ E. Na₂SO₃

E. Na₂SO₃

Using the data in the table, which of the conjugate acids below is the strongest acid? Base Kb ClO- 3.3 x 10^-7 CO3^-2 1.8 x 10^-4 HS- 1.8 x 10^-7 NH2CH3 4.4 x 10^-4

H2S

Of the following, the entropy of ________ is the largest.

H2S (g) A) H20 (s) B) H2S (g) C) H20 (g) D) H2S (s) E) H20 (l)

Oxidation Numbers HBrO

H= 1+ Br= 1+ O= 2-

Oxidation numbers HAsCl₄

H=1+ As= 3+ Cl= -1

A- is a weak base. Which equilibrium corresponds to the equilibrium constant Ka for HA?

HA (aq) + H2O (l) = H3O+ (aq) + A- (aq)

The addition of sodium hydroxide and ______ to water produces a buffer solution. HCl NaC2H3O2 NaF HC7H5O2 NaCl

HC7H5O2

7 strong acids

HCl HBr HI HNO3 H2SO4 HClO3 HClO4 completely dissociate in a solution

Of the following which is the strongest acid? (2nd)

HClO4

Of the following _______ is a weak acid. (1st)

HF

Of the following, ____ is a weak acid.

HF

Of the following acids, _____ is not a strong acid.

HNO2

The conjugate base of H2PO4- is ____.

HPO4^-2

the time required for the concentration of a reactant to drop to one-half of its original value.

Half-Life t_1/2 for 1st order - 1/2 life depends only on the rate constant and not on the initial concentration: t 1/2 = 0.693/k. for 2nd order - 1/2 life depends on both the rate constant and the initial concentration of A: t 1/2 = 1/k[A]o

2 or more phases present are called

Heterogeneous Equilibria

Corrosion of iron is retarded by

High pH conditions

A solution containing a nonvolatile solute possesses a ------ ------- ------- than the pure solvent.

Higher Boiling Point

Equilibria where all substances are in same phase are called

Homogenous Equilibria

Those that do not dissolve significantly in one another are

Immiscible

the buffering capacity is significantly decreased.

In a solution, when the concentrations of a weak acid and its conjugate base are equal,

the -log of the [H+] and the -log of the Ka are equal

In a solution, when the concentrations of a weak acid and its conjugate base are equal, ________. A) the system is not at equilibrium B) the buffering capacity is significantly decreased C) the -log of the [H+] and the -log of the Ka are equal D) All of the above are true.

goes down regardless of whether the reaction is exothermic or endothermic

In general, as activation energy increases, reaction rate ________. A) goes down if the reaction is exothermic B) goes down if the reaction is endothermic C) stays the same regardless of whether the reaction is exothermic or endothermic D) goes down regardless of whether the reaction is exothermic or endothermic E) none of the above

for a basic solution pH _______ and pOH ___________ at 25 degree celsius

pH > 7 and pOH < 7 at 25 degree celsius

The Ka of HF is 6.8 x 10^(-4). What is the pH of a 0.35 M solution of HF?

pH+ 1.82

Calculate the pH of a 0.35 M aqueous solution of CH3NH2 (Methlamine) . The Kb of methlamine is 4.4 x 10^(-4)

pH= 12.08

The Henderson-Hasselbalch equation is _________

pH= p K(a) + log ( [base] / [ acid] )

Henderson-Hasselbalch Equation

pH= pKa + log [base]/[acid]

When talking about buffers, it is best to choose an acid with a ____ close to the desired pH.

pKa

The unit cell with all sides the same length and all angles equal to 90° that has lattice points only at the corners is called __________.

primitive cubic

Arrhenius base

produces OH- (hydroxide) ions in water

The equilibrium constant for the gas phase reaction 2 SO2 (g) + O2 (g) = 2 SO3 (g) is Keq = 2.80 x 10^2 at 999 K. At equilibrium, __________.

products predominate

If the reaction quotient Q for a reaction is greater than the value of the equilibrium constant K for that reaction at a given temperature, __________ must be converted to _________ for the system to reach equilibrium.

products, reactants

In which of the following aqueous solutions would you expect AgCl to have the highest solubility? a. pure water b. 0.020 M BaCl2 c. 0.015 NaCl d. 0.020 AgNO3 e. 0.020 KCl

pure water

In which of the following aqueous solutions would you expect AgCl to have the highest solubility?

pure water

Which of the following aqueous solutions has the highest [OH- ] ?

pure water

Of the following, only __________ is not a state function.

q

_______ analysis is designed to detect the presence of metal ions.

qualitative

________ analysis is designed to determine how much metal ion is present.

quantitative

An instantaneous reaction rate is the

rate at a particular moment in the reaction and is usually determined graphically.

As the temperature of a reaction is increased, the rate of the reaction increases because the

reactant molecules collide more frequently and with greater energy per collision

If the temperature of a system at equilibrium is increased, the system reacts as if we added a ________ to an endothermic reaction or a _______ to an exothermic reaction.

reactant, product

If the reaction quotient Q for a reaction is less than the value of the equilibrium constant K for that reaction at a given temperature, __________ must be converted to _________ for the system to reach equilibrium.

reactants, products

elementary reaction

reactions that occur in a single event or step

strong base

readily accepts a proton forming a WEAK conjugate acid OH - strong base H20- weak c.a weak base - ammonia

When Pressure is applied to a gas, its volume

readily decreases

At constant temperature, reducing the volume of a gaseous equilibrium mixture causes the system to shift in the direction that __________ the number of moles of gas.

reduces

The gain of electrons by an element is called

reduction

Heat + NH₄Cl (s) ↔ NH₃ (g) + HCl (g) if heat is added to the reaction, will the reaction shift to the right, left, or no change

right

Increasing T in an endothermic reaction causes the equilibrium to shift _____.

right

For a reaction where overall reaction order is 1, k has units

s-1

Ions can be separated from each other based on their ______ ___________.

salt solubilities

Removal of one metal ion from a solution is called ___________ __________.

selective precipitation

If volume increases then pressure decreases so equilibrium will :

shift in direction of larger # of moles of gas (in case of 2NO + O2 <-->2NO2 left) K stays same

H₂ (g) + I₂(g) ↔ 2HI 9G) + heat if heat is added to the reaction, will the reaction shift to the right, left, or no change

shifts to the left

H₂ (g) + I₂(g) ↔ 2HI 9G) + heat If the concentration of H₂ (g) is increased, will the reaction shift to the right, left, or no change?

shifts to the right

Human blood is __________.

slightly basic

Human blood is __________. a. neutral b. very basic c. slightly acidic d. very acidic e. slightly basic

slightly basic

The rate limiting step in a reaction is the ________ step in the reaction sequence.

slowest

Which of the following could be added to a solution of acetic acid to prepare a buffer? a. sodium hydroxide b. hydrochloric acid c. nitric acid d. more acetic acid e. None of the above can be added to an acetic acid solution to prepare a buffer.

sodium hydroxide

The strongest interparticle attractions exist between particles of a __________ and the weakest interparticle attractions exist between particles of a __________.

solid, gas

N2 (g) + 3 H2 (g) 2 NH3 (g)

Of the following equilibria, only __________ will shift to the right in response to a decrease in volume.

0.821 M HC2H3O2 and 0.713 M NaC2H3O2

Of the following solutions, which has the greatest buffering capacity? A) 0.521 M HC2H3O2 and 0.217 M NaC2H3O2 B) 0.821 M HC2H3O2 and 0.713 M NaC2H3O2 C) 0.365M HC2H3O2 and 0.497 M NaC2H3O2 D) 0.121 M HC2H3O2 and 0.116 M NaC2H3O2

0.543 M NH3 and 0.555 M NH4Cl

Of the following solutions, which has the greatest buffering capacity? A) 0.543 M NH3 and 0.555 M NH4Cl B) 0.087 M NH3 and 0.088 M NH4Cl C) 0.234 M NH3 and 0.100 M NH4Cl D) 0.100 M NH3 and 0.455 M NH4Cl E) They are all buffer solutions and would all have the same capacity.

sucrose

Of the following, a 0.1 M aqueous solution of __________ will have the highest freezing point.

1.6

On a clear day at sea level, with a temperature of 25 °C, the partial pressure of N2 in air is 0.78 atm and the concentration of nitrogen in water is 5.3 × 10-4 M. When the partial pressure of N2 is __________ atm, the concentration in water is 1.1 × 10-3 M.

If one of the ions in a solution equilibrium is already dissolved in the solution, the equilibrium will shift to the left and the solubility of the salt will decrease.

The common-ion effect

3.0 x 10-2 mol/L-atm

The concentration of CO2 in a soft drink bottled with a partial pressure of CO2 of 4.0 atm over the liquid at 25 °C is 1.2 x 10-1 M. The Henry's law constant for CO2 at this temperature is __________.

the relative magnitudes of cohesive forces in the liquid and adhesive forces between the liquid and its container

The shape of a liquid's meniscus is determined by

At constant T and V, Ptotal of a gas sample is determined by what?

The total # of moles of gas present, whether the total represents just one gas or a mixture of gases.

3.81

The value of Keq for the equilibrium CO2 (g) + 2H2 (g) CH3OH (g) is 14.5 at 483 °C. What is the value of Keq for the equilibrium below? 1/2 CO2 + H2 (g) 1/2 CH3OH (g)

You have a solution of 34.5 % by mass H3PO4 (Mol mass = 98) with a density of 1.211 g/mL. Calculate M and m.

To calculate M, take 1 L of solution. How many g of H3PO4 are present? (1211 g)(0.345) = 417.8 g H3PO4 How many moles of H3PO4 are present? 417.8 g (1 mol/98 g) = 4.26 mol We took 1 L of solution so M = 4.26 M

False

True or False The solubility of slightly soluble salts containing basic anions is proportional to the pH of the solution.

True

True or False? Emulsifying agents typically have a hydrophobic end and a hydrophilic end.

Which of the following equations is correct? a. ΔG° = ΔH° − TΔS° b. ΔH° = ΔG° − TΔS° c. ΔG° = ΔH° − ΔS° d. ΔG° = ΔH° − ΔS°/T

a

Which of the following has the highest bond dissociation energy? a. HF b. HCl c. HBr d. HI

a

Which of the following is a definition of the activation energy of a reaction? a. the difference in Gibbs free energy between the reactants and the transition state b. the difference in Gibbs free energy between the reactants and the intermediate c. the difference in Gibbs free energy between the reactants and the product d. the difference in Gibbs free energy between the transition state and the product

a

Which of the following is a feature of a Brønsted-Lowry acid? a. proton donor b. proton acceptor c. electron pair donor d. electron pair acceptor

a

Which of the following substituents has the highest priority according to the Cahn-Ingold-Prelog system used in assigning R and S configurations? a. −COOH b. −CHO c. −CH2OH d. −CH3

a

How many kinds of atoms are represented in the equation 2CO + O₂ --> 2CO₂? a. 2 b. 3 c. 5 d. more than 5

a (2 - O & C)

Which of the following substances would probably have a pH of 11 or higher? a. KOH b. tap water c. orange juice d. HCL

a (KOH)

If it could dissolve in water, the molecule that formed from these two element would most likely be: a. an electrolyte b. a nonelectrolyte

a (an electrolyte)

Which of the following foods has the greatest concentration of H+ ions? a. apricot - pH 2.0 b. bread - pH 5.5 c. corn - pH 6.2 d. milk - pH 6.8

a (apricot - pH 2.0 because acids (lower pH number) have a higher concentration of H+ ions than bases)

The only particle of an atom that is involved in a covalent bond is the: a. electrons b. protons c. neutrons d. nucleus

a (electrons)

Hydrogen bonding occurs in water when the: a. hydrogen of one water molecule is attracted to the oxygen of another water molecule. b. two hydrogens of one water molecule are attracted to each other. c. hydrogens of one water molecule are attracted to the hydrogens of another molecule. d. the hydrogen and oxygen atoms of the same molecule are attracted to each other.

a (hydrogen of one water molecule is attracted to the oxygen of another water molecule)

The most likely kind of bond to form between these two atoms would be: a. ionic b. polar covalent c. nonpolar covalent d. weak hydrogen

a (ionic)

The atom that can form a metal ion is: a. lithium b. chlorine c. neither can form a metal ion d. both can form metal ions

a (lithium)

Which of the following molecular characteristics would NOT be given by the formula C₆H₁₂O₆? a. position of atoms b. number of atoms c. kinds of atoms d. numerical proportions of atoms

a (position of atoms)

It is most likely that a molecule formed from these two elements would be: a. soluble in water b. insoluble in water c. soluble in a nonpolar solvent

a (soluble in water)

Consider the following reaction at equilibrium: 2 NH3 (g) = N2 (g) + 3 H2 (g) Delta H = + 92.4 kJ Le Châtelier's principle predicts that adding N2 (g) to the system at equilibrium will result in __________.

a decrease in concentration of H2 (g)

Consider the following reaction at equilibrium: 2SO₂ (g) + O₂ (g) ↔ 2SO₃ (g) delta H° = -99 kj Le Chatelier's principle predicts that an increase in temperature will result in______.

a decrease in the partial pressure of SO₃

Consider the following reaction at equilibrium: 2NH3 (g) N2 (g) + 3H2 (g) Le Châtelier's principle predicts that the moles of H2 in the reaction container will increase with ________

a decrease in the total pressure (T constant)

What do amphoteric acids dissolve in?

a strong acid or base

what is a buffer

a weak acid and its conjugate base; or a weak base and its conjugate acid

Which of the following is a redox reaction a. Cu + AgNO₃ → 2Ag + Cu(NO₃)₂ b. HCl + NaOH → H₂O + NaCl c. AgNO₃ + HCl → AgCl + HNO₃ d. H₂CO₃ + Ca(NO₃)₂ → 2HNO₃ + CaCO₃

a. Cu + AgNO₃ → 2Ag + Cu(NO₃)₂

Classify each process as an endothermic or exothermic process. a. forming solute-solvent attractions b. breaking solute-solute attractions c. breaking solvent-solvent attractions

a. Exothermic b. Endothermic c. Endothermic

Of the following, ____ is a weak acid a. HF b. HBr c. HClO4 d. HNO3

a. HF

Factors affecting reaction rates are:

a. Nature of reactants b. Concentration c. Surface area d. Temp e. Catalyst

Which of the following reactions will produce more products when the pressure is increased? a. P₄ (s) +6Cl₂ (g) ↔ 4PCl₃ (l) b. PCl₃ (g)+ 3NH₃ (g) ↔ P(NH₂)₃ (g) + 3HCl (g) c. 4HCl (g)+ O₂ (g)↔ 2H₂O (g) + 2Cl₂ (g) d. 2H₂O₂ (l)↔ 2H₂O (l) + O₂ (g)

a. P₄ (s) +6Cl₂ (g) ↔ 4PCl₃ (l)

Which one of the following will change the vale of an equilibrium constant? a. changing temperature b. adding other substances that do not react with any of the species involved in the equilibrium c. varying the initial concentrations of reactants d. varying the initial concentrations of products

a. changing temperature

In the Bronsted-Lowry Definition, an acid is a substance that a. Donates H+. b.accepts H+ ions c. neutralizes hydronium ions d. forms a slalt

a. donates H+ ions

Reduction involves the ___ of electrons a. gain b. loss c. displacement d. bonding

a. gain

a homogeneous equilibrium is where the reactants and products are a. in the same state b. in different states c. not equal d. unstable

a. in the same state

If Q is less than Keq, the reaction a. proceeds to the right b. proceeds to the left c. has reached equilibrium d. has come to completion

a. proceeds to the right

The reaction: A + B ↔ X + Y Keq= 997 at 472. at equilibrium a. products are predominate b. reactants are predominate c. roughly equal molar amounts of products and reactants are present d. only products exist

a. products are predominate

The reaction quotient is used to determine if the reaction has a. reached equilibrium b. come to completion c. stopped reacting d. none of the above

a. reached equilibrium

A/an _____ agent is a substance that has the potential to cause another substance to be oxidized a. reducing b. oxidizing c. biological d. chemical

a. reducing

At chemical equilibrium a. the rate of the forward reaction is equal to the rate of the reverse reaction b. the concentration of the reactants are equal to the concentration of the products c. the reaction stops d. the rate of the forward reaction becomes much greater than the reverse reaction

a. the rate of the forward reaction is equal to the rate of the reverse reaction

In the reaction Zn + H₂SO₄ → ZnSO₄ + H₂, which if any element is oxidized? a. zinc b. hydrogen c. sulfur d. oxygen e. none of these

a. zinc

The uptake of molecules into the interior of another substance is referred to as _______.

absorption

Base

accepts a proton from HCl

Which of the following could be added to a solution acetate to produce a buffer?

acetic acid or hydrochloric acid

Which of the following could be added to a solution of sodium acetate to produce a buffer? acetic acid only acetic acid or hydrochloric acid hydrochloric acid only potassium acetate only sodium chloride or potassium acetate

acetic acid or hydrochloric acid

Although CaCO3 has a relatively small solubility product, it is quite soluble in the presence of __________.

acid

Monoprotic

acid that contains ONE acidic proton HCl

Tripotic

acid that contains THREE acidic protons H3PO4

Diprotic

acid that contains TWO acidic protons H2SO4

If a substance has a basic anion, i will be more soluble in a(n) ______ solution.

acidic

if [H30+] > 1.0 x 10^-7 M then the solution is

acidic

if [OH-] < 1.0 x 10^-7 M then the solution is

acidic

metals with charges 3+ or higher will make a solution

acidic

pH < 7

acidic

pOH > 7

acidic

acidity trend on the periodic table

acidity increases from left to right and from top to bottom most acidic bottom right

The minimum energy to initiate a chemical reaction is the _________ energy.

activation

A Bronsted-Lowry base is defined as a substance that ____.

acts as a proton acceptor

A Bronsted-Lowry acid is defined as a substance that ____.

acts as a proton donor

Which of the following terms describes the reactivity of trimethylamine, (CH3)3N? a. Brønsted-Lowry acid and Lewis acid b. Brønsted-Lowry base and Lewis base c. Lewis acid and not a Brønsted-Lowry acid d. Lewis base and not a Brønsted-Lowry base

b

How many kinds of molecules are represented in the equation 2CO + O₂ --> 2CO₂? a. 2 b. 3 c. 5 d. more than 5

b (3 - CO, O₂, and CO₂)

How many electrons does phosphorous (P) have in its valence shell? a. 15 b. 5 c. 7 d. 8

b (5)

An element that has an atomic number of 8 would have: a. an atomic mass of 8 b. 8 protons c. 8 neutrons d. 4 electrons and 4 protons

b (8 protons)

Is phosphorous more likely to form an: a. positive cation b. negative anion c. no ions can form from phosphorus

b (negative anion)

How would you determine if a substance formed electrolytes in water? a. see if it dissolved in water b. see if it dissolves in water and conducts an electric current c. examine the chemical formula to see if it is an organic molecule, because only organic molecules form electrolytes in water d. observe whether it is hydrophobic or hydrophilic, because only hydrophobic molecules can form electrolytes

b (see if it dissolves in water and conducts an electric current)

The energy which can be used by living things exists as the energy: a. of the nucleus of the atoms b. that bonds one atom to another c. of motions, which all atoms have d. stored in molecules in the form of heat

b (that bonds one atom to another - chemical energy)

What makes water polar? a. it is an ionic compound b. the electrons are shared unequally c. the molecules tend to be cohesive d. it is made of nonmetals

b (the electrons are shared unequally)

Calculate the hydrogen ion concentration of an aqeous solution, given the concentration of hydroxide ions is 1.0 x 10^(-5). a. 1.0 x 10^9-5) b. 1.0 x 10^(-9) c. 1.0 x 10^(5) d. 1.0 x 10^(9)

b. 1.0 x 10^(-9)

an aqeous solution contains 0.00250 M HCl. What is the pH of the solution? a. 3.40 b. 2.60 c. -2.60 d. -3.40

b. 2.60

By definition an Arrhenius Acid a. produces OH- ions b. produces H+ ions c. accepts H+ ions d. accepts OH- ions

b. Produces H+ ions

An aqueous solution contains 0.10 M NaOH. The solution is ___. a. very dilute b. basic c. neutral d. acidic

b. basic

The species formed when a Bronsted-Lowry base gains a proton is a. conjugate base b. conjugate acid c. weak acid d. weak base

b. conjugate acid

Consider r x n: CO2 + H2 --> CO + H2O If all species are gases and CO2 is removed, the [CO] at equilibrium will: a. increase b. decrease c. remain unchanged d. disappear

b. decrease

A heterogeneous equilibrium is where the reactants are products are a. in the same state b. in different states c. not equal d. unstable

b. in different states

Oxidation involves the ____ of electrons a. gain b. loss c. displacement d. bending

b. loss

____ numbers are based on the distribution of electrons in a molecule a. coefficient b. oxidation c. electron d. chemical

b. oxidation

A/an _____ agent is a substance that has the potential to cause another substance to be reduced. a. reducing b. oxidizing c. chemical d. biological

b. oxidizing

The reaction : X + Y ↔2Z has Keq = 4.34 x 10⁻³ at 550 K. at equilibrium, a. products are predominate b. reactants are predominate c. roughly equal amounts of products and reactants are present d. only products are present

b. reactants are predominate

if [H3O+] < 1.0 X 10^-7 M then the solution is

basic

if [OH-] > 1.0 x 10^-7 M then the solution is

basic

Elementary reactions involving the simultaneous collision of two molecules are __________.

bimolecular

litmus paper changes

blue paper will turn red below ph5 red paper turns blue above ph 8 acid blue

the amount of acid or base the buffer can neutralize before the pH begins to change to an appreciable degree

buffer capacity

A catalyst can increase the rate of a reaction __________.

by providing an alternative pathway with a lower activation energy

molecularity or the reaction is defined

by the number of molecules that participate as reactants in an elementary reactions

How many isomers (constitutional and stereoisomers) exist for dimethylcyclopentane? a. 3 b. 5 c. 7 d. 9

c

How many stereoisomers of 2,3-butanediol, CH3CH(OH)CH(OH)CH3, exist? a. 1 b. 2 c. 3 d. 4

c

How many stereoisomers of 2,4-pentanediol, CH3CH(OH)CH2CH(OH)CH3, exist? a. 1 b. 2 c. 3 d. 4

c

Which of the following anions is the strongest base? a. CH3COO− b. HO− c. NH2− d. Cl−

c

Which of the following has a pKa value of approximately 16? a. HBr b. CH3COOH c. CH3CH2OH d. HC≡CH

c

Which of the following has a pKa value of approximately 25? a. CH3CH3 b. CH2=CH2 c. HC≡CH d. CH3CH2OH

c

Which of the following is a definition of the rate-determining step of a reaction mechanism? a. the first step b. the last step c. the step that crosses the highest energy barrier d. the most exothermic step

c

Which of the following is a feature of a Lewis base? a. proton donor b. proton acceptor c. electron pair donor d. electron pair acceptor

c

Which of the following is present in the highest concentration upon dissolution of H2SO4 in water? a. H2SO4 b. H+ c. H3O+ d. HO−

c

Which of the following is present in the highest concentration upon dissolution of acetic acid in water? a. OH− b. H3O+ c. CH3COOH d. CH3COOH+

c

At constant temperature, increasing the volume of a gaseous equilibrium mixture causes the system to shift in the direction that __________ the number of moles of gas.

increases

A reaction was found to be second order in carbon monoxide concentration. The rate of the reaction _________ if [CO] is doubled, with everything else kept the same.

increases by a factor of 4

As pH decreases, [H+] ________ and solubility ________.

increases; increases

how does reactant temperature affect reaction rates?

increasing temperatures increases the kinetic energy of the reactant molecules. this causes them to collide more frequently, thus increasing the reaction rate

For the endothermic reaction CaCO3 (s) = CaO (s) + CO2 (g) Le Châtelier's principle predicts that __________ will result in an increase in the number of moles of CO2.

increasing the temperature

Enthalpy change

indicates how an increase in temperature affects the equilibrium

A large value of Kc

indicates the equilibrium mixture contains more products than reactants and therefore lies toward the product side of equation

A small value of Kc

indicates the equilibrium of the mixture contains less products than reactants and therefore lies toward reactant side

Based on solubilities, _____ can be selectively removed from solutions

ions

The overall reaction order ____ the sum of the orders of each reactant in the rate law.

is

buffer

is a solution containing a weak acid and one of its salts or a weak base and one of its salts. This solution is able to neutralize acids and bases without allowing the pH of the solution to change greatly

catalyst

is a substance that changes the speed of a chemical reaction without undergoing a permanent chemical change itself.

The empirical formula of an addition polymer __________.

is the same as that of the monomer from which it is formed

overall reaction order

is the sum of the orders with respect to each reactant represented in the rate law

The monomer that is polymerized to make natural rubber is __________.

isoprene

a buffer resits changes in pH because.....

it contains both an acid to neutralize added OH- ions and a base to neutralize added H+ ions. The acid and base that make p the buffer, must not consume each other through a neutralization reaction. This is fufilled b a weak acid base conjugate pair such as Ch3COOH and CH3COO- or NH4+ and NH3

a buffer rests changes in pH because....

it contains both an acid to neutralize added OH⁻ ions and a base to neutralize added H⁺ ions. The acid and base that make up the buffer, however, must not consume each other through a neutralization reactions.

One can use differences in ______ of _____ to separate ions in a mixture.

solubilities of salts

strong bases

soluble hydroxides which are the alkali metal and heavy alkaline earth metals ( Ca2+, Sr2+, Ba2+) completely dissociate in a solution

buffers

solutions of a weak conjugate acid-base pair

The process of solute particles being surrounded by solvent particles is known as __________.

solvation

For the reaction C2H6 (g) --> C2H4 (g) + H2 (g) Delta H° is +137 kJ/mol and Delta S° is +120 J/K * mol. This reaction is ____.

spontaneous only at high temperature

weak acids have ____ conjugate bases

strong

weak bases have _____ conjugate acids

strong

A common ion can be removed by adding a _______ _____.

strong acid

Hydroxides and oxides of Al3+, Cr3+, Zn2+, and Sn2+ are examples of what?

strong acids or bases that amphoteric acids will dissolve in

The extent of ionization of a weak electrolyte is decreased by adding to the solution a _____ _______ that has an ion in common with the weak electrolyte.

strong electrolyte

Which of the following is not a type of solid?

supercritical

first-order reaction rate constant unit

s⁻¹

to get the value of k

take rate from any trial and use [ ] from trial and calculate. Make sure you put in calculator correctly. Ex: (9.0*10^-3)/((0.50^2)(0.030)) = 1.2 which is correct value of k. then plug into rate equation Ex: k[A]^2[B] --> 1.2((0.50^2)(0.075)) = 2.3*10^-2 which is right in this situation.

In general, the vapor pressure of a substance increases as __________ increases.

temperature

Elementary reactions involving the simultaneous collision of three molecules are ________

termolecular

If Ea = 105 kJ and ΔE = -15 kJ for the forward reaction then Ea for the reverse reaction is 120 kJ

true

If a reaction is second order in A and third order for B the rate increases 72 times on tripling the concentration of A and doubling [B]

true

If the reaction quotient Q for a reaction is less than the value of the equilibrium constant K for that reaction at a given temperature, reactants must be converted to products for the system to reach equilibrium

true

Pure solids and pure liquids are excluded from the equilibrium-constant expressions

true

The half-life of a second order reaction equals The half-life of a second order reaction equals

true

The number obtained by substituting starting reactant and product concentrations into an equilibrium-constant expression is known as the reaction quotient

true

The rate of a reaction increases approximately eight times when the temperature is raised by 30 degrees

true

_ In an exothermic equilibrium reaction, increasing the reaction temperature favors the formation of reactants

true

The acid-dissociation constant, Ka , for gallic acid is 4.57 × 10-3. What is the base-dissociation constant, Kb, for the gallate ion?

tweet 2.19

Which one of the following statements regarding Kw is false? A) pKw is 14.00 at 25 °C B) The value of Kw is always 1.0 × 10-14. C) Kw changes with temperature. D) The value of Kw shows that water is a weak acid. E) Kw is known as the ion product of water.

B

Which solution below has the highest concentration of hydroxide ions? A) pH = 3.21 B) pH = 12.6 C) pH = 7.93 D) pH = 9.82 E) pH = 7.00

B

For the following reaction, how does the rate of appearance of CO2 relate to the rate of disappearance of CH3OH? 2CH3OH + 3O2 --------> 2CO2 + 4H2O

∆ [CO2]/∆t = - 2/2 ∆ [CH3OH] / ∆t

A solution is prepared by dissolving 14.0 g of NH₃ in 250.0 g of water. The density of the resulting solution is 0.974 g/mL. The mole fraction of NH₃ in the solution is __________. A) 0.0550 B) 0.0560 C) 16.8 D) 0.940 E) 0.922

B) 0.0560

31) In which of the following aqueous solutions would you expect AgBr to have the lowest solubility? A) pure water B) 0.20 M NaBr C) 0.10 M AGNO3 D) 0.15 M KBr E) 0.10 M LiBr

B) 0.20 M NaBr

10) Which one of the following statements regarding is false? A) is 14.00 at 25 °C B) The value of is always 1.0 × 10-14. C) changes with temperature. D) The value of shows that water is a weak acid. E) is known as the ion product of water.

B) The value of is always 1.0 × 10-14.

A- is a weak base. Whuich equilibrium corresponds to the equilibrium constant Ka for HA? A) HA (aq) + H2O (l) <--> H2A+ (aq) OH- (aq) B) A- (aq) + H3O+ (aq) <--> HA (aq) + H2O (l) C) HA (aq) + H2O (l) <--> H3O+ (aq) + A- (aq) D) A- (aq) + H2O (l) <--> HA (aq) + OH- (aq) E) A- (aq) + OH- (aq) <--> HOA^2- (aq)

C

An aqueous solution contains 0.10 M NaOH. The solution is __________. A) very dilute B) highly colored C) basic D) neutral E) acidic

C

In basic solution, __________. A) [H3O+] = [OH-] B) [H3O+] > [OH-] C) [H3O+] < [OH-] D) [H3O+] = OM E) [OH-] > 7.00

C

A substance that is capable of acting as both an acid and as a base is __________. A) autosomal B) conjugated C) amphoteric D) saturated E) miscible

C

Identify the acid, base, conjugate acid, and conjugate base in the following reactions. CO3^(-2) + H2O <---> HCO3^(-) + OH^(-)

CO3= base H2O= acid HCO3= conjugate acid OH= conjugate base

Which one of the following is not amphoteric? a. Al(OH)3 b. Ca(OH)2 c. Cr(OH)3 d. Zn(OH)2 e. Sn(OH)2

Ca(OH)2

For which salt should the aqueous solubility be most sensitive to pH? a. Ca(NO3)2 b. CaF2 c. CaCl2 d. CaBr2 e. CaI2

CaF2

Which compound listed below has the greatest molar solubility in water? a. CdCO3 b. Cd(OH)2 c. AgI d. CaF2 e. ZnCO3

CaF2

You dissolve 9.00 g of urea (molar mass = 60.0) in 10.0 mL of water. If the vapor pressure of pure water at 24 ˚C is 22.4 mm Hg, what will the vapor pressure of the solution be?

Calculate moles of Urea : 0.15mol Calculate moles of water: 0.556mol Calculate mole fraction of water: 0.556/(0.556 + 0.15) = 0.788 Calculate new pressure: 0.788 x 22.4mmHg = 17.6mmHg

75.8

Calculate the enthalpy change (in kJ) associated with the conversion of 25.0 grams of ice at -4.00 °C to water vapor at 106.0 °C. The specific heats of ice, water, and steam are 2.09 J/g-K, 4.18 J/g-K, and 1.84 J/g-K, respectively. For H2O, Hfus = 6.01 kJ/mol and Hvap = 40.67 kJ/mol.

-0.316

Calculate the freezing point of a 0.08500 m aqueous solution of NaNO3. The molal freezing-point-depression constant of water is 1.86 °C/m.

3.05 m

Calculate the molality of a 10.0% (by mass) aqueous solution of hydrochloric acid.

0.0589

Calculate the mole fraction of phosphoric acid (H3PO4) in a 25.4% (by mass) aqueous solution.

0.0937

Calculate the percent ionization of formic acid (HCO2H) in a solution that is 0.311 M in formic acid and 0.189 M in sodium formate (NaHCO2). The Ka of formic acid is 1.77 × 10-4.

What does Amphiprotic mean?

Can behave as an acid or a base

An aqueous solution of __________ will produce a basic solution. A) NH4ClO4 B) KBr C) NaCl D) NaHSO4 E) Na2SO3

E

1. On a clear day at sea level, with a temperature of 25 °C, the partial pressure of N2 in air is 0.78 atm and the concentration of nitrogen in water is 5.3 x 10-4 M. When the partial pressure of N2 is __________ atm, the concentration in water is 1.1 x 10-3 M. A) 0.63 atm B) 0.78 atm C) 1.0 atm D) 2.1 atm E) 1.6 atm

E. 1.6 atm

Which of the following compounds is the strongest acid? a. CF3OH b. CF3CH2 CH2OH c. CF3CH2 CH2 CH2OH d. CF3CH2 CH2 CH2CH2OH

a

Which of the following compounds is the strongest acid? a. HF b. H2O c. NH3 d. CH4

a

A burning splint will burn more vigorously in pure oxygen than in air because A) oxygen is a reactant in combustion and concentration of oxygen is higher in pure oxygen than is in air. B) oxygen is a catalyst for combustion. C) oxygen is a product of combustion. D) nitrogen is a product of combustion and the system reaches equilibrium at a lower temperature. E) nitrogen is a reactant in combustion and its low concentration in pure oxygen catalyzes the combustion.

A

Consider the following reaction at equilibrium: 2SO2 (g) + O2 (g) <--> 2SO3 (g) ΔH° = -99 kJ Le Chatelier's principle predicts that an increase in temperature will result in __________. A) a decrease in the partial pressure of SO3 B) a decrease in the partial pressure of C) an increase in SO2 D) no changes in equilibrium partial pressures Keq E) the partial pressure of O2 will decrease

A

Consider the following reaction: 3A → 2B The average rate of appearance of B is given by Δ[B]/Δt. Comparing the rate of appearance of B and the rate of disappearance of A, we get Δ[B]/Δt = _____ × (-Δ[A]/Δt). A) +2/3 B) -2/3 C) -3/2 D) +1 E) +3/2

A

Consider the following reaction: A → 2C The average rate of appearance of C is given by Δ[C]/Δt. Comparing the rate of appearance of C and the rate of disappearance of A, we get Δ[C]/Δt = _____ × (Δ[A]/Δt). A) +2 B) +1/2 C) -1 D) +1 E) -1/2

A

For the elementary reaction NO3 + CO --> NO2 + CO2 the molecularity of the reaction is __________, and the rate law is A) 2, k[NO3][CO] B) 4, k[NO3][CO][NO2][CO2] C) 2, k[NO2][CO2] D) 2, k[NO3][CO] / [NO2][CO2] E) 4, k[NO2][CO2] / [NO3][CO]

A

For the endothermic reaction CaCO3 (s) <--> CaO (s) + CO2 (g) Le Chatelier's principle predicts that __________ will result in an increase in the number of moles of CO2 . A) increasing the temperature B) decreasing the temperature C) increasing the pressure D) removing some of the CaCO3 (s) E) none of the above

A

Of the compounds below, a 0.1 M aqueous solution of __________ will have the highest pH. A) KCN , Ka of HCN = 4.0 x 10-10 B) NH4NO3 , Kb of NH3 = 1.8 x 10-5 C) NaOAc , Ka of HOAc = 1.8 x 10-5 D) NaClO , Ka of HClO = 3.2 x 10-8 E) NaHS , Kb of HS- = 1.8 x 10-7

A

Of the following acids, __________ is not a strong acid. A) HNO2 B) H2SO4 C) HNO3 D) HClO4 E) HCl

A

Of the following, __________ is a weak acid. A) HF B) HCl C) HBr D) HNO3 E) HClO4

A

Of the following, all are valid units for a reaction rate except __________. A) mol/L B) M/s C) mol/hr D) g/s E) mol/L-hr

A

3) Consider a solution containing 0.100 M fluoride ions and 0.126 M hydrogen fluoride. The concentration of hydrogen fluoride after addition of 5.00 mL of 0.0100 M HCl to 25.0 mL of this solution is __________ M. A) 0.107 B) 0.100 C) 0.126 D) 0.00976 E) 0.00193

A) 0.107

The Henry's law constant for helium gas in water at 30 °C is 3.70 ×10⁻⁴ M/atm. When the partial pressure of helium above a sample of water is 0.650 atm, the concentration of helium in the water is __________ M. A) 2.41 × 10⁻⁴ B) 3.70 ×10⁻⁴ C) 1.76 × 10³ D) 5.69 × 10⁻⁴ E) 1.30

A) 2.41 × 10⁻⁴

Calculate the molarity of a 10.0% (by mass) aqueous solution of hydrochloric acid. A) 3.04 m B) 4.33 m C) 0.274 m D) 2.74 m E) The density of the solution is needed to solve the problem.

A) 3.04 m

Calculate the molality of a 17.5% (by mass) aqueous solution of nitric acid. A) 3.37 B) 0.212 C) 0.278 D) 2.78 E) The density of the solution is needed to solve the problem.

A) 3.37

A solution is prepared by dissolving 22.7 g of CaCl₂ in 375 g of water. The density of the resulting solution is 1.05 g/mL. The concentration of CaCl₂ is __________% by mass. A) 5.71 B) 6.24 C) 0.0571 D) 0.0599 E) 5.99

A) 5.71

Of the following, a 0.1 M aqueous solution of __________ will have the lowest freezing point. A) Al(NO₃)₃ B) NaCl C) Na₂SO₄ D) K₂CrO₄ E) sucrose

A) Al(NO₃)₃

51) Which of the following acids will be the strongest? A) H2SO4 B) HSO4- C) H2SO3 D) H2SEO4 E) HSO3-

A) H2SO4

28) Classify the following compounds as weak bases (W) or strong bases (S): ammonia flouride ion sodium hydroxide A) W W S B) S S S C) S W W D) W S S E) W S W

A) W W S

The dissolution of water in octane (C₈H₁₈) is prevented by: A) hydrogen bonding between water molecules B) ion-dipole attraction between water and octane molecules C) London dispersion forces between octane molecules D) dipole-dipole attraction between octane molecules E) repulsion between like- charged water and octane molecules

A) hydrogen bonding between water molecules

15) Which of the following could be added to a solution of acetic acid to prepare a buffer? A) sodium hydroxide B) hydrochloric acid C) nitric acid D) more acetic acid E) None of the above can be added to an acetic acid solution to prepare a buffer.

A) sodium hydroxide

22) Classify the following compounds as weak acids (W) or strong acids (S): hydrocyanic acid hydrofluroic acid phenol A) W W W B) S S S C) S W W D) W S S E) W S W

A)W W W

HA is a weak acid. Which equilibrium corresponds to the equilibrium constant Kb for A-?

A- (aq) + H2O (l) = HA (aq) + OH- (aq)

A- what is the concentration of H+ ions in a 1.5 M aqueous solution of HClO. Ka is 3.0 x 10^9-8). B- what is the percent ionization of hypoclorous acid?

A- 2.1 x 10^(-4) B- 0.014 %

5. Which of the following aqueous solutions will have the highest boiling point? A) 0.10 m Na2SO4 B) 0.20 m glucose C) 0.25 m sucrose D) 0.10 m NaCl E) 0.10 m SrSO4

A. 0.10m Na2SO4

6. Nitrogen dioxide decomposes to nitric oxide and oxygen via the reaction: 2NO2 → 2NO + O2 In a particular experiment at 300 °C, [NO2 ]drops from 0.0100 to 0.00650 M in 100 s. The rate of appearance of O2 for this period is __________ M/s. A) 1.8 × 10−5 B) 3.5 × 10−5 C) 7.0 × 10−5 D) 1.8 x 10-3 E) 7.0 × 10−3

A. 1.8 x 10-5

Which of the following will change the value of an equilibrium constant? A. Changing Temperature B. Adding other substances that don't react with any of the species involved in the equilibrium C. Varying the initial [ ] of reactants D. Varying the initial [ ] of products E. Changing the volume of the reaction vessel F. Adding a Catalyst

A. Changing Temperature

Which one of the following will change the value of an equilibrium constant? A. Changing temperature B. Varying initial concentration of products C. Adding other substances that do not react with any of the species involved D. Varying the initial concentration of reactants E. Changing the volume of the reaction vessel

A. Changing temperature

Which of the following expressions is the correct equilibrium-constant expression for the equilibrium between dinitrogen tetroxide and nitrogen dioxide? N2O4 (g) ⇌ 2NO2 (g) A. [NO2]²/[N2O4] B. [NO2]/[N2O4]² C. [NO2]²[N2O4] D. [NO2][N2O4] E. [NO2]/[N2O4]

A. [NO2]²/[N2O4]

V = nRT/P

(1.00mol)(0.08206)(273.15K)/1.00atm = 22.4L (STP - Standard Temperature and Pressure)

37. A 0.100 m solution of which one of the following solutes will have the lowest vapor pressure?

(B) Al(ClO4)3

23. Which of the following substances is least likely to dissolve in water?

(B) CCl4

28. The concentration of CO2 in a soft drink bottled with a partial pressure of CO2 of 6.5 atm over the liquid at 29 °C is 2.2 ⋅ 10-1 M. The Henry's law constant for CO2 at this temperature is:

(C) 3.4 x 10-3 mol/ L-atm

factors affecting solubility

- the common ion effect if one of the ions in a solution equilibrium is already dissolved in the solution,the equilibrium will shift to the left and the solubility of the salt will decrease -pH if a substance has a basic anion it will be soluble in a more acidic solution substances with acidic cations dissolve better in basic solutions. -complex ions metal ions can act as Lewis acids and form complex ions with Lewis bases in the solvent; formation of complex ions increase the solubility of these salts -amphoterism amphoteric metal oxides and hydroxides are soluble in strong acid or base because they can act as either acids or bases Examples Al3+, Zn2+, Sn2+

give an expression that relates the rate of disappearance of each reactant to the rate of appearance of each product. 2 NO + Cl2 --------> 2 NOCl

-1/2∆[NO] / ∆t = -∆[Cl2] / ∆t = ∆1/2 [NOCl] / ∆t

Use the table below to answer the questions that follow. Thermodynamic Quantities for Selected Substances at 298.15 K (25 °C) Substances Delta H°f (kJ/mol) Delta G°f (kJ/mol) S (J/K-mol) Carbon C (s, diamond) 1.88 2.84 2.43 C (s, graphite) 0 0 5.69 C2H2 (g) 226.7 209.2 200.8 C2H4 (g) -84.68 -32.89 229.5 CO (g) -110.5 -137.2 197.9 CO2 (g) -393.5 -394.4 213.6 Hydrogen H2 (g) 0 0 130.58 Oxygen O2 (g) 0 0 205.0 H2O (l) -285.83 -237.13 69.91 The value of Delta S° for the catalytic hydrogenation of acetylene to ethene, C2H2 (g) + H2 (g) --> C2H4 (g) is ____ J/K mol.

-112.0

The standard cell potential (E°cell) of the reaction below is +0.126 V. The value of \Delta G^\circ Δ G for the reaction is __________ kJ/mol. Pb(s)+H^+ (aq)----> Pb^(2+) (aq) + H2 (g)

-24.3

The value of Delta G° at 373 K for the oxidation of solid elemental sulfur to gaseous sulfur dioxide, S (s, rhombic) + O2 (g) --> SO2 (g) is ____ kJ/mol. At 298 K, Delta H° for this reaction is -269.9 kJ/mol, and Delta S° is +11.6 J/K.

-274.2

Use the table below to answer the questions that follow. Thermodynamic Quantities for Selected Substances at 298.15 K (25 °C) Substances Delta H°f (kJ/mol) Delta G°f (kJ/mol) S (J/K-mol) Calcium Ca (s) 0 0 41.4 CaCl2 (s) -795.8 -748.1 104.6 Chlorine Cl2 (g) 0 0 222.96 Oxygen O2 (g) 0 0 205.0 H2O (l) -285.83 -237.13 69.91 Phosphorus P2 (g) 144.3 103.7 218.1 PCl3 (g) -288.1 -269.6 311.7 POCl3 (g) -542.2 -502.5 325 Sulfur S (s, rhombic) 0 0 31.88 SO2 (g) -269.9 -300.4 248.5 SO3 (g) -395.2 -370.4 256.2 The value of Delta G° at 25 °C for the oxidation of solid elemental sulfur to gaseous sulfur trioxide, 2 S (s, rhombic) + 3 O2 (g) --> 2 SO3 (g) is ____ kJ/mol.

-740.8

Oxyacids are named by changing the end of the name of the polyatomic ion from....

-ate to -ic acid OR -ite to -ous acid

cations reacting with water

-cations with acidic protons ( like ammonia ) will lower the pH of a solution (becomes more acidic) -most metal cations that are hydrated will also lower the pH of a solution

arrhenius theory drawbacks:

-only defines acids and bases with WATER as a solvent -H+ must be present to define a substance as an acid -OH- must be present to define a substance as a base -the theory does not explain the basicity of ammonia or acidity of BF2, Al3+, Fe3+

give an expression that relates the rate of disappearance of each reactant to the rate of appearance of each product. PCl3 + Cl2 --------> PCl5

-∆[PCl3] / ∆t = -∆[Cl2] / ∆t = ∆[PCl5] / ∆t

19) Which one of the following is a Br nsted-Lowry acid? A) (CH3)3NH+ B) CH3COOH C) HF D) HNO2 E) all of the above

...

Consider the decomposition of acetaldehyde CH3CHO → CH4 + CO [CH3CHO], M Rate M/s 0.10 0.02 0.20 0.08 0.30 0.182 Determine the rate law, the reaction order and the rate constant

...

The kinetics of the reaction below were studied and it was determined that the reaction rate increased by a factor of 9

...

The Keq for the equilibrium below is 0.112 at 700.0 °C. What is the value of Keq at this temperature for the following reaction?

0.0125

A flask is charged with 0.124 mol of A and allowed to react to form B according to the reaction A(g) --> B(g). The following data are obtained for [A] as the reaction proceeds: Time (s) 0.00 10.0 20.0 30.0 40.0 Moles of A 0.124 0.110 0.088 0.073 0.054 How many moles of B are present at 10 s?

0.014

20. In which of the following aqueous solutions would you expect PbCl2to have the lowest solubility? a. 0.020 M KCl b. 0.020 M BaCl2 c. 0.015 M PbNO3 d. pure water e. 0.015 M NaCl

0.020 M BaCl2

In which of the following aqueous solutions you expect AgCl to have the lowest solubility? a. pure water b. 0.020 M BaCl2 c. 0.015 NaCl d. 0.020 AgNO3 e. 0.020 KCl

0.020 M BaCl2

A solution is prepared by dissolving 23.7 g of CaCl2 in 375 g of water. The density of the resulting solution is 1.05 g/mL. The mole fraction of Cl- in this solution is __________ .

0.0200

Calculate the mole fraction of phosphoric acid (H3PO4) in a 25.4% (by mass) aqueous solution.

0.0589

Given the reaction A(g) ----> 2B(g) and the number of moles of A at different times is as follows, time 0 5 min 10 min moles A 0.100 0.085 0.070 what is the number of moles of B at 10 min if there were no moles of B initially present?

0.060 mol We have reacted 0.030 mol of A, and the number of moles of B formed is double this amount.

The value of Keq for the following reaction is 0.25: SO2 (g) + NO2 (g) = SO3 (g) + NO (g) The value of Keq at the same temperature for the reaction below is ____. 2 SO2 (g) + 2 NO2 (g) = 2 SO3 (g) + 2 NO (g)

0.063

The value of Keq for the following reaction is 0.25: SO₂ (g) + NO₂ (g) ↔ SO₃ (g) + NO (g) The value of Keq at the same temperature for the reaction below is what? 2SO₂ (g) + 2NO₂ (g) ↔ 2SO₃ (g) + 2NO (g)

0.063

A weak acid has a pKa of 4.289. If the solution pH is 3.202, what percentage of the acid is dissociated?

8.2%

What is the pH of an aqueous solution at 25 °C that contains 3.98 x 10^-9 M hydronium ion?

8.400

Calculate the pH of a 0.0887 M aqueous sodium cyanide solution at 25.0 °C. Kb for CN− is 4.9⋅10^−10.

8.82 Kb = [HCN][OH-]/[CN-] pOH = -log[OH-] pH = 14 - pOH

One difference between first- and second-order reactions is that __________. A) the half-life of a first-order reaction does not depend on ; the half-life of a second-order reaction does depend on B) the rate of both first-order and second-order reactions do not depend on reactant concentrations C) the rate of a first-order reaction depends on reactant concentrations; the rate of a second-order reaction does not depend on reactant concentrations D) a first-order reaction can be catalyzed; a second-order reaction cannot be catalyzed E) None of the above are true.

A

The kinetics of the reaction below were studied and it was determined that the reaction rate did not change when the concentration of B was tripled. The reaction is __________ order in B. A + B → P A) zero B) first C) second D) third E) one-half

A

The reaction below is exothermic: 2SO2 (g) + O2 (g) <--> 2SO3 (g) Le Chatelier's Principle predicts that __________ will result in an increase in the number of moles of SO3 (g) in the reaction container. A) increasing the pressure B) decreasing the pressure C) increasing the temperature D) removing some oxygen E) increasing the volume of the container

A

Which of the following acids will be the strongest? A) H2SO4 B) HSO4- C) H2SO3 D) H2SeO4 E) HSO3-

A

Which of the following is true? A) If we know that a reaction is an elementary reaction, then we know its rate law. B) The rate-determining step of a reaction is the rate of the fastest elementary step of its mechanism. C) Since intermediate compounds can be formed, the chemical equations for the elementary reactions in a multistep mechanism do not always have to add to give the chemical equation of the overall process. D) In a reaction mechanism, an intermediate is identical to an activated complex. E) All of the above statements are true.

A

__________ are used in automotive catalytic converters. A) Heterogeneous catalysts B) Homogeneous catalysts C) Enzymes D) Noble gases E) Nonmetal oxides

A

Al(ClO4)3

A 0.100 m solution of which one of the following solutes will have the lowest vapor pressure?

Endothermic

A description of a change in which a system absorbs energy from its surroundings (Absorbs Heat)

Exothermic

A description of a change in which a system releases energy to its surroundings (Gives off Heat)

1.92 × 10³

A particular first-order reaction has a rate constant of 1.35 × 102 s⁻¹ at 25.0°C. What is the magnitude of k at 65.0°C if Ea = 55.5 kJ/mol? A) 1.92 × 10³ B) 1.95 × 10⁴ C) 358 D) 3.48 × 10⁷³ E) 1.35 × 10²

3.34 × 10³

A particular first-order reaction has a rate constant of 1.35 × 102 s⁻¹ at 25.0°C. What is the magnitude of k at 75.0°C if Ea = 55.3 kJ/mol? A) 2.24 × 10⁴ B) 3.34 × 10³ C) 433 D) 2.49 × 10⁶ E) 1.35 × 10²

2) The presence of a dipole moment

A polar molecule will interact with water molecules which also have a dipole moment. Dipole moments are caused by the close proximity of electronegative atoms such as oxygen or sulfur to less electronegative atoms such as hydrogen or carbon. Acetone, H3C(CO)CH3 and methanol, HOCH3, are readily soluble in water due to their dipole moments from the presence of the electronegative oxygen atom. On the other hand, a molecule like butane, CH3CH2CH2CH3, which has no dipole moment, is hydrophobic and hence insoluble in water.

increase by a factor of 27

A reaction was found to be third order in A. Increasing the concentration of A by a factor of 3 will cause the reaction rate to ________. A) remain constant B) increase by a factor of 27 C) increase by a factor of 9 D) triple E) decrease by a factor of the cube root of 3

remain constant

A reaction was found to be zero order in A. Increasing the concentration of A by a factor of 3 will cause the reaction rate to ________. A) remain constant B) increase by a factor of 27 C) increase by a factor of 9 D) triple E) decrease by a factor of the cube root of 3

none of the above

A solution containing which one of the following pairs of substances will be a buffer solution? A) KI, HI B) AgBr, HBr C) CuCl, HCl D) CsI, HI E) none of the above

CsF, HF

A solution containing which one of the following pairs of substances will be a buffer solution? A) NaI, HI B) KBr, HBr C) RbCl, HCl D) CsF, HF E) none of the above

196 g/mol

A solution is prepared by dissolving 6.00 g of an unknown nonelectrolyte in enough water to make 1.00 L of solution. The osmotic pressure of this solution is 0.750 atm at 25.0 °C. What is the molecular weight (g/mol) of the unknown solute?

2SO2 (g) + O2 (g) 2SO3 (g) Le Chatelier's Principle predicts that __________ will result in an increase in the number of moles of SO3 (g) in the reaction container. A. increasing the pressure B. increasing the volume of the container C. removing some oxygen D. decreasing the pressure E. increasing the temperature

A. increasing the pressure

According to the Arrhenius concept, an acid is a substance that _____. A. is capable of donating one or more H⁺ B. can accept a pair of electrons to form a coordinate covalent bond C. reacts with solvent to form the cation formed by the auto-ionization of that solvent. D. causes an increase in the concentration of H⁺ in aqueous solutions E. tastes bitter

A. is capable of donating one or more H⁺

1.79 × 10-5

Acetic acid is a weak acid that dissociates into the acetate ion and a proton in aqueous solution: HC2H3O2 (aq) C2H3O2- (aq) + H+ (aq) At equilibrium at 25 °C a 0.100 M solution of acetic acid has the following concentrations: [HC2H3O2] = 0.0990 M, [C2H3O2-] = 1.33 × 10-3 M, and [H+] = 1.33 × 10-3 M. The equilibrium constant, Keq, for the ionization of acetic acid at 25°C is __________.

Collision with energy, Ea, or greater can cause atoms of the colliding molecules to reach the =

Activated Complex (transition state) which is the highest energy arrangement in the pathway from reactants to products.

site of the enzyme where the catalysis occurs is called =

Active Site

Which compound listed below has the smallest molar solubility in water? a. ZnCO3 b. Cd(OH)2 c. CdCO3 d. AgI e. CaF2

AgI

A 0.100 m solution of which one of the following solutes will have the lowest vapor pressure?

Al(CIO4)3

4.79

At 20 °C, an aqueous solution that is 24.0% by mass in ammonium chloride has a density of 1.0674 g/mL. What is the molarity of ammonium chloride in the solution? The formula weight of NH4Cl is 53.50 g/mol.

160

At elevated temperatures, methylisonitrile (CH₃NC) isomerizes to acetonitrile (CH₃CN): CH₃NC (g) → CH₃CN (g) The dependence of the rate constant on temperature is studied and the graph below is prepared from the results. The energy of activation of this reaction is ________ kJ/mol. A) 160 B) 1.6 × 10⁵ C) 4.4 × 10⁻⁷ D) 4.4 × 10⁻⁴ E) 1.9 × 10⁴

As the temperature of a reaction is increased, the rate of the reaction increases because the __________. A) reactant molecules collide less frequently B) reactant molecules collide more frequently and with greater energy per collision C) activation energy is lowered D) reactant molecules collide less frequently and with greater energy per collision E) reactant molecules collide more frequently with less energy per collision

B

At equilibrium, __________. A) all chemical reactions have ceased B) the rates of the forward and reverse reactions are equal C) the rate constants of the forward and reverse reactions are equal D) the value of the equilibrium constant is 1 E) the limiting reagent has been consumed

B

Consider the following reaction at equilibrium: 2NH3 (g) <--> N2 (g) + 3H2 (g) ΔH° = +92.4 kJ Le Chatelier's principle predicts that adding N2 (g) to the system at equilibrium will result in __________. A) a decrease in the concentration of NH3 (g) B) a decrease in the concentration of H2 (g) C) an increase in the value of the equilibrium constant D) a lower partial pressure of N2 E) removal of all of the H2 (g)

B

Consider the following reaction at equilibrium: 2NH3 (g) <--> N2 (g) + 3H2 (g) Le Chatelier's principle predicts that the moles of H2 in the reaction container will increase with __________. A) some removal of NH3 from the reaction vessel (V and T constant) B) a decrease in the total pressure (T constant) C) addition of some N2 to the reaction vessel (V and T constant) D) a decrease in the total volume of the reaction vessel (T constant) E) an increase in total pressure by the addition of helium gas (V and T constant)

B

In the Arrhenius equation, K = Ae^-Ea/RT __________ is the frequency factor. A) k B) A C) e D) Ea E) R

B

In the energy profile of a reaction, the species that exists at the maximum on the curve is called the __________. A) product B) activated complex C) activation energy D) enthalpy of reaction E) atomic state

B

Of the following equilibria, only __________ will shift to the left in response to a decrease in volume. A) H2 (g) + Cl2 (g) <--> 2HCl (g) B) 2SO3 (g) <--> 2SO2 (g) + O2 (g) C) N2 (g) + 3H2 (g) <--> 2NH3 (g) D) 4Fe (s) + 3O2 (g) <--> 2Fe2O3 (s) E) 2HI (g) <--> H2 (g) + I2 (g)

B

Of the following, which is the strongest acid? A) HIO B) HIO4 C) HIO2 D) HIO3 E) The acid strength of all of the above is the same.

B

Of the units below, __________ are appropriate for a first-order reaction rate constant. A) Ms-1 B) s-1 C) mol/L D) M-1s-1 E) L mol-1 s-1

B

The Ka for formic acid (HCHO2) is 1.8x10 to the negative 4. What is the pH of a 0.35-M aqueous solution of sodium formate (NaCHO2)? A) 5.36 B) 8.64 C) 10.71 D) 4.20

B

The data in the table below were obtained for the reaction: A + B → P Experiment Number [A] (M) [B] (M) Initial Rate (M/s) 1 0.273 0.763 2.83 2 0.273 1.526 2.83 3 0.819 0.763 25.47 The order of the reaction in A is __________. A) 1 B) 2 C) 3 D) 4 E) 0

B

The equilibrium constant for the gas phase reaction N2 (g) + 3H2 (g) <--> 2NH3 (g) is Keq = 4.34 x 10^-3 at 300 °C. At equilibrium, __________. A) products predominate B) reactants predominate C) roughly equal amounts of products and reactants are present D) only products are present E) only reactants are present

B

The molar concentration of hydronium ion in pure water at 25degreesC is __________. A) 7.00 B) 1.0x10^-7 C) 1.00 D) 1.0x10^-14

B

The overall order of the reaction is __________. A) 1 B) 2 C) 3 D) 4 E) 0

B

The rate law of a reaction is rate = k[D][X]. The units of the rate constant are __________. A) mol L -1s1 B) L mol-1 s1 C) mol^2 L^-2 s^1 D) mol L^-1 s^2 E) L^2 mol^-2 s^1

B

The rate law of the overall reaction A + B --> C is rate k[A]^2. Which of the following will not increase the rate of the reaction? A) increasing the concentration of reactant A B) increasing the concentration of reactant B C) increasing the temperature of the reaction D) adding a catalyst for the reaction E) All of these will increase the rate.

B

Which of the following expressions is the correct equilibrium-constant expression for the equilibrium between dinitrogen tetroxide and nitrogen dioxide? N2O4 (g) <--> 2NO2 (g) A) [NO2] / [N2O4] B) [NO2]^2 / [N2O4] C) [NO2] / [N2O4]^2 D) [NO2] [N2O4] E) [NO2]^2 [N2O4]

B

Which of the following statements is false? A) The solubility of a gas increases in direct proportion to its partial pressure above the solution. B) The weaker the attraction between the solute and solvent molecules, the greater the solubility. C) Substances with similar intermolecular attractive forces tend to be soluble in one another. D) The solubility of gases in water decreases with increasing temperature. E) Non polar liquids tend to be insoluble in polar liquids.

B) The weaker the attraction between the solute and solvent molecules, the greater the solubility.

The process of a substance sticking to the surface of another is called A) adsorption B) absorption C) effusion D) coagulation E) diffusion

B) absorption

13) Which of the following could be added to a solution of sodium acetate to produce a buffer? A) acetic acid only B) acetic acid or hydrochloric acid C) hydrochloric acid only D) potassium acetate only E) sodium chloride or potassium acetate

B) acetic acid or hydrochloric

25) A 25.0 mL sample of a solution of a monoprotic acid is titrated with a 0.115 M NaOH solution. The titration curve above was obtained. Which of the following indicators would be best for this titration? A) methyl red B) bromthymol blue C) thymol blue D) phenolpthalein E) bromocresol purple

B) bromthymol blue

20) Which one of the following will cause hemoglobin to release oxygen? A) increase in pH B) decrease in pH C) decrease in temperature D) decrease in CO2 concentration E) increase in O2 concentration

B) decrease in pH

The Procter & Gamble Company product called olestraTM is formed by combining a sugar molecule with: A) protein B) fatty acids C) cholesterol D) alcohols E) vitamin A

B) fatty acids

An unsaturated solution is one that: A) contains no solute B) has a concentration lower than the solubility C) has no double bonds D) contains the maximum concentration of solute possible, and is in equilibrium with undissolved solute E) contains more dissolved solute than the solubility allows

B) has a concentration lower than the solubility

18) What are the principal organs that regulate the pH of the carbonic acid-bicarbonate buffer system in the blood? A) kidneys, liver B) lungs, kidneys C) spleen, liver D) lungs, skin E) brain stem, heart

B) lungs, kidneys

Molality is defined as the: A) moles solute/liters solution B) moles solute/kg solvent C) moles solute/moles solvent D) moles solute/kg solution E) none (dimensionless)

B) moles solute/kg solvent

16) Which of the following could be added to a solution of acetic acid to prepare a buffer? A) sodium acetate only B) sodium acetate or sodium hydroxide C) nitric acid only D) hydrofluoric acid or nitric acid E) sodium hydroxide only

B) sodium acetate or sodium hydroxide

In a saturated solution of a salt in water: A) seed crystal addition may cause massive crystallization B) the rate of crystallization = the rate of dissolution C) addition of more water causes massive crystallization D) the rate of dissolution > the rate of crystallization E) the rate of crystallization> the rate of dissolution

B) the rate of crystallization = the rate of dissolution

What is the pH of a 0.0150 M aqueous solution of barium hydroxide? A. 12.2 B. 12.5 C. 1.82 D. 1.52 E. 10.4

B. 12.5

At equilibrium, __________. A. All chemical reactions have ceased. B. The rates of the forward and reverse reactions are equal. C. The rate constants of the forward and reverse reactions are equal. D. The value of the equilibrium constant is 1. E. The limiting reagent has been consumed

B. The rates of the forward and reverse reactions are equal.

2CO2 (g) 2CO (g) + O2 (g) ΔH° = -514 kJ Le Chatelier's principle predicts that an increase in temperature will __________. A. increase the partial pressure of CO B. decrease the value of the equilibrium constant C. decrease the partial pressure of CO2 (g) D. increase the value of the equilibrium constant E. increase the partial pressure of O2 (g)

B. decrease the value of the equilibrium constant

Which solution below has the highest concentration of hydroxide ions? A. pH = 7 B. pH = 12.6 C. pH = 9.82 D. pH = 7.93 E. pH = 3.21

B. pH = 12.6

The magnitude of Kw indicated that _____. A. the auto-ionization of water is exothermic B. water auto-ionizes only to a very small extent C. water auto-ionizes very quickly D. Water auto-ionizes very slowly

B. water auto-ionizes only to a very small extent

1) According to the Arrhenius concept, an acid is a substance that __________. A) is capable of donating one or more B) causes an increase in the concentration of in aqueous solutions C) can accept a pair of electrons to form a coordinate covalent bond D) reacts with the solvent to form the cation formed by autoionization of that solvent E) tastes bitter

B.causes an increase in the concentration of H+ in aquaeous solutions

40

Based on the figure above, the boiling point of diethyl ether under an external pressure of 1.32 atm is __________°C.

In which of the following aqueous solutions does the weak acid exhibit the highest percentage ionization? A) 0.01 M HC2H3O2 (Ka = 1.8 x 10-5) B) 0.01 M HNO2 (Ka = 4.5 x 10-4) C) 0.01 M HF (Ka = 6.8 x 10-4) D) 0.01 M HClO (Ka = 3.0 x 10-8) E) These will all exhibit the same percentage ionization.

C

Nitric acid is a strong acid. This means that __________. A) aqueous solutions of HNO3 contain equal concentrations of and B) HNO3 does not dissociate at all when it is dissolved in water C) HNO3 dissociates completely to H+ (g) and NO3- (aq) when it dissolves in water D) HNO3 produces a gaseous product when it is neutralized E) HNO3 cannot be neutralized by a weak base

C

Nitrogen fixation is a difficult process because __________. A) there is so little nitrogen in the atmosphere B) nitrogen exists in the atmosphere primarily as its oxides which are very unreactive C) nitrogen is very unreactive, largely due to its triple bond D) of the extreme toxicity of nitrogen E) of the high polarity of nitrogen molecules preventing them from dissolving in biological fluids, such as those inside cells

C

Of the following, __________ will lower the activation energy for a reaction. A) increasing the concentrations of reactants B) raising the temperature of the reaction C) adding a catalyst for the reaction D) removing products as the reaction proceeds E) increasing the pressure

C

The data in the table below were obtained for the reaction: exp, [ClO2](M), [OH-](M), Initial Rate (M/s) 1, 0.060, 0.030, 0.0248 2, 0.020, 0.030, 0.00276 3, 0.020, 0.090, 0.00828 What is the order of the reaction with respect to ClO2? A) 1 B) 0 C) 2 D) 3 E) 4

C

The following reaction occurs in aqueous solution: NH4+ (aq) + NO2- → N2 (g) + 2H2O (l) The data below is obtained at 25°C. [NH4+](M) [NO2-](M) Initial rate (M/s) 0.0100 0.200 3.2 × 10-3 0.0200 0.200 6.4 × 10-3 The order of the reaction in NH4+ is __________. A) -1 B) 0 C) +1 D) +2 E) -2

C

The kinetics of the reaction below were studied and it was determined that the reaction rate increased by a factor of 9 when the concentration of B was tripled. The reaction is __________ order in B. A + B → P A) zero B) first C) second D) third E) one-half

C

The magnitude of Kw indicates that __________. A) water autoionizes very slowly B) water autoionizes very quickly C) water autoionizes only to a very small extent D) the autoionization of water is exothermic

C

The rate law for a reaction is rate = k[A][B]2 Which one of the following statements is false? A) The reaction is first order in A. B) The reaction is second order in B. C) The reaction is second order overall. D) k is the reaction rate constant E) If [B] is doubled, the reaction rate will increase by a factor of 4.

C

What is the pH of an aqueous solution at 25degreesC in which [OH-] is 0.0025 M? A) +2.60 B) -2.60 C) +11.40 D) -11.40

C

The concentration of nitrate ion in a solution that contains 0.900 M aluminum nitrate is _____M. A) 0.450 B) 0.900 C) 2.70 D) 1.80 E) 0.300

C) 2.70

The concentration of CO₂ in a soft drink bottled with a partial pressure of CO₂ of 6.5 atm over the liquid at 29 °C is 2.2 x 10-1 M. The Henry's law constant for CO₂ at this temperature is: A) 5.6 x 10-3 mol/L-atm B) 7.6 x 10-3 mol/L-atm C) 3.4 x 10-2 mol/L-atm D) 2.2 x 10-1 mol/L-atm E) More information is needed to solve the problem.

C) 3.4 x 10-2 mol/L-atm

Which one of the following is most soluble in water? A) CH3CH2CH2CH2OH B) CH3CH2OH C) CH3OH D) CH3CH2CH2OH E) CH3CH2CH2CH2CH2OH

C) CH3OH

A 1.35 m aqueous solution of compound X had a boiling point of 101.4 °C. Which one of the following could be compound X? The boiling point elevation constant for water is 0.52 °C/m. A) Na3PO4 B) CH3CH2OH C) KCl D) CaCl2 E) C6H12O6

C) KCl

11) The addition of hydrochloric acid and __________ to water produces a buffer solution. A) HC6H5O B) NaOH C) NH3 D) HNO3 E) NANO3

C) NH3

Of the following, a 0.2 M aqueous solution of __________ will have the highest freezing point. A) Na₃PO₄ B) Mg(NO₃)₂ C) NaCl D) (NH₄)₃PO₄ E) Pb(NO₃)₂

C) NaCl

10) The addition of hydrofluoric acid and __________ to water produces a buffer solution. A) HCl B) NANo3 C) NaF D) NaCl E) NaBr

C) NaF

. 12) An aqueous solution contains 0.10 M NaOH. The solution is __________. A) very dilute B) highly colored C) basic D) neutral E) acidic

C) basic

13) Nitric acid is a strong acid. This means that __________.

C) dissociates completely to and when it dissolves in water

14) Which of the following could be added to a solution of potassium fluoride to prepare a buffer? A) sodium hydroxide B) potassium acetate C) hydrochloric acid D) sodium fluoride E) ammonia

C) hydrochloric acid

A supersaturated solution: A) must be in contact with undissolved solid B) is one with more than one solute C) is one with a higher concentration than the solubility D) is one that has been heated E) exists only in theory and cannot actually be prepared

C) is one with a higher concentration than the solubility

Ammonium nitrate dissolves readily in water even though the dissolution is endothermic by 26.4 kJ/mol. The solution process is spontaneous because: A) of the decrease in enthalpy upon addition of the solute B) of the increase in enthalpy upon dissolution of this strong electrolyte C) of the increase in disorder upon dissolution of this strong electrolyte D) the vapor pressure of the water decreases upon addition of the solute E) osmotic properties predict this behavior

C) of the increase in disorder upon dissolution of this strong electrolyte

Write the chemical equation of the following gaseous homogeneous equilibrium expressions [CH₄] [H₂O] / [CO] [H₂]³

CO(g) + 3H₂ (g) ↔ CH₄ (g) + H₂) (g)

40) Why does fluoride treatment render teeth more resistant to decay? A) Fluoride kills the bacteria in the mouth that make the acids that decay teeth. B) Fluoride stimulates production of tooth enamel to replace that lost to decay. C) Fluoride reduces saliva production, keeping teeth drier and thus reducing decay. D) Fluoride converts hydroxyapatite to fluoroapatite that is less reactive with acids. E) Fluoride dissolves plaque, reducing its decaying contact with teeth.

C) that the selective precipitation of a metal ion, such as , is promoted by the addition of an appropriate counterion that produces a compound (AgX) with a very low solubility

Colligative properties of solutions include all of the following except: A) depression of vapor pressure upon addition of a solute to a solvent B) elevation of the boiling point of a solution upon addition of a solute to a solvent C) the increase of reaction rates with increase in temperature D) an increase in the osmotic pressure of a solution upon the addition of more solute E) depression of the freezing point of a solution upon addition of a solute to a solvent

C) the increase of reaction rates with increase in temperature

A solution contains 15 ppm of benzene. The density of the solution is 1.00 g/mL. This means that: A) the solution is 15% by mass of benzene B) the molarity of the solution is 15 C) there are 15 mg of benzene in 1.0 L of this solution D) 100 g of the solution contains 15 mg of benzene E) 100 g of the solution contains 15 g of benzene

C) there are 15 mg of benzene in 1.0 L of this solution

7) The magnitude of indicates that __________. A) water autoionizes very slowly B) water autoionizes very quickly C) water autoionizes only to a very small extent D) the autoionization of water is exothermic

C) water autoionizes only to a very small extent

The value of Keq for the following reaction is 0.25: SO2 (g) + NO2 (g) SO3 (g) + NO (g) The value of Keq at the same temperature for the reaction below is __________. 2SO2 (g) + 2NO2 (g) 2SO3 (g) + 2NO (g) A. 0.12 B. 0.25 C. 0.062 D. 0.50 E. 16

C. 0.062

Ka of HF at 25°C is 6.8 x 10⁻⁴. What is the pH of a 0.35 M aqueous solution of HF? A. 12 B. 3.2 C. 1.8 D. 3.6 E. 0.46

C. 1.8

The Keq for the equilibrium below is 7.52 × 10-2 at 480 °C. 2Cl2 (g) + 2H2O (g) ⇌ 4HCl (g) + O2 (g) What is the value of Keq at this temperature for the following reaction? 2HCl (g) + 1/2 O₂ (g) ⇌ Cl₂ (g) + H₂O (g) A. -0.0376 B. 0.274 C. 3.65 D. 13.3 E. 5.66

C. 3.65

The base-dissociation constant, Kb, for pyridine, C₅H₅N, is 1.4 x 10⁻⁹. The Ka for pyridinium, C₅H₅NH⁺ is _____. A. 1.4 x 10⁻²³ B. 1.0 x 10⁻⁷ C. 7.1 x 10⁻⁶ D. 1.4 x 10⁻⁵ E. 7.1 x 10⁻⁴

C. 7.1 x 10⁻⁶

3. Which one of the following substances would be the most soluble inCCl4 ? A) CH3CH2OH B) H2O C) NH3 D) C10H22 E) NaCl

C. C10H22

2NH₃ ⇌ N₂ (g) + 3 H₂ (g) DeltaH = +92.4 kJ Le Chateliers principle predicts that adding N₂ (g) to the system at equilibrium will result in: A. Removal of all H₂ (g) B. An increase in the value of the equilibrium constant. C. Decrease in H₂ (g) concentration D. Decrease in NH₃ (g) concentration E. Lower partial pressure of N₂ (g)

C. Decrease in H₂ (g) concentration

Which one of the following is true concerning the Haber process? A. It is another way of stating Le Chatelier's principle. B. It is a process used for shifting equilibrium positions to the right for more economical chemical synthesis of a variety of substances. C. It is a process used for the synthesis of ammonia. D. It is a process for the synthesis of elemental chloride. E. It is an industrial synthesis of sodium chloride that was discovered by Karl Haber.

C. It is a process used for the synthesis of ammonia.

In which of the following reactions would increasing pressure at constant temperature not change the concentrations of reactants and products, based on Le Chatelier's principle? A. 2N2 (g) + O2 (g) 2N2O (g) B. N2 (g) + 3H2 (g) 2NH3 (g) C. N2 (g) + O2 (g) 2NO (g) D. N2O4 (g) 2NO2 (g) E. N2 (g) + 2O2 (g) 2NO2 (g)

C. N2 (g) + O2 (g) 2NO (g)

N2 (g) + 3H2 (g) 2NH3 (g) is Keq = 4.34 × 10-3 at 300 °C. At equilibrium, __________. A. roughly equal amounts of products and reactants are present B. products predominate C. reactants predominate D. only reactants are present E. only products are present

C. Reactants Predominate

At equilibrium, __________. A. all chemical reactions have ceased B. the rate constants of the forward and reverse reactions are equal C. the rates of the forward and reverse reactions are equal D. the value of the equilibrium constant is 1 E. the limiting reagent has been consumed

C. the rates of the forward and reverse reactions are equal

Which one of the following is least soluble in water?

C10H22 (the largest of the given substances, smaller substances are generally more soluble than larger substances)

Using the data in the table, which of the conjugate acids below is the strongest acid?

C5H5NH+

Of the following, __________ should have the highest critical temperature.

CBr4

Of the following substances, only __________ has London dispersion forces as its only intermolecular force.

CH4

A physical property of a solution that depends on the concentration of solute particles present, regardless of the nature of the solute is a -----

Colligative Property (Colligative properties include vapor-pressure lowering, freezing-point lowering, boiling-point elevation, and osmotic pressure.

Assumes that reactions occur as a result of sollisions between molecules, helps explain why the magnitudes of rate constants increase with increasing temperature.

Collision Model

Reaction rates are affected by reactant concentrations and temperature. This is accounted for by the ______.

Collision model

increase the partial pressure of CO2 (g) at equilibrium

Consider the following reaction at equilibrium: 2CO2 (g) 2CO (g) + O2 (g) H° = -514 kJ Le Châtelier's principle predicts that adding O2 (g) to the reaction container will __________.

Consider the reaction: N2 (g) + O2 (g) ∏ 2NO (g) Kc = 0.1 If you start 0.81 M N2 and 0.81 M O2 what will the concentrations of all species be at equilibrium?

Cpd [ ]i Δ[ ] [ ]eq N2 0.81 -x 0.81-x 0.70 O2 0.81 -x 0.81-x 0.70 NO 0.00 +2x +2x 0.22 K=[NO]2 / [N2][O2] Plug in Equil. concentrations and solve for x. Check to see if you can take the square root of both sides. X=0.11

Calculating equilibrium constants: Consider the reaction: 2 NO (g) + 2H2 (g) --><-- N2 (g) + 2H2O (g) You put 0.10 M NO, 0.050 M H2, and 0.10 M H2O in a reaction. At equilibrium the [NO] is 0.062 M. Calculate Kc

Cpd [ ]i Δ[ ] [ ]eq NO 0.10 0.038 0.062 H2 0.05 0.038 0.012 N2 0.00 0.019 0.019 H2O 0.10 0.038 0.138 Now use the equilibrium concentrations calculate Kc : Kc = 654

Oxidation numbers Cr₂O₇⁻²

Cr= 6= 0=2-

Equilibrium between a saturated soln. and undissolved solute is dynamic; the process of soln. and the reverse process ------- occurs simultaneously.

Crystallization

A solution containing which one of the following pairs of substances will be a buffer solution? NaI & HI KBr & HBr RbCl & HCl CsF HF none of the above

CsF

For a first-order reaction, a plot of __________ versus __________ is linear. A) In [A]t,1/t B) t,1/[A]t C) [A]t, t D) ln [A]t, t E) 1/[A]t , t

D

A catalyst can increase the rate of a reaction __________. A) by changing the value of the frequency factor (A) B) by increasing the overall activation energy (Ea) of the reaction C) by lowering the activation energy of the reverse reaction D) by providing an alternative pathway with a lower activation energy E) All of these are ways that a catalyst might act to increase the rate of reaction.

D

A reaction was found to be third order in A. Increasing the concentration of A by a factor of 3 will cause the reaction rate to __________. A) triple B) remain constant C) decrease by a factor of the cube root of 3 D) increase by a factor of 27 E) increase by a factor of 9

D

A reaction was found to be zero order in A. Increasing the concentration of A by a factor of 3 will cause the reaction rate to __________. A) triple B) decrease by a factor of the cube root of 3 C) increase by a factor of 27 D) remain constant E) increase by a factor of 9

D

At 400 K, the equilibrium constant for the reaction Br2 (g) + Cl2 (g) <--> 2BrCl (g) is Kp = 7.0p. A closed vessel at 400 K is charged with 1.00 atm of Br2 (g), 1.00 atm of Cl2 (g), and 2.00 atm of BrCl (g). Use Q to determine which of the statements below is true. A) The equilibrium partial pressures of Br2, Cl2 , and BrCl will be the same as the initial values. B) The equilibrium partial pressure of Br2 will be greater than 1.00 atm. C) At equilibrium, the total pressure in the vessel will be less than the initial total pressure. D) The equilibrium partial pressure of BrCl (g) will be greater than 2.00 atm. E) The reaction will go to completion since there are equal amounts of Br2 and Cl2.

D

Consider the following reaction at equilibrium: 2CO2 (g) <--> 2CO (g) + O2 (g) ΔH° = -514 kJ Le Chaelier's principle predicts that adding (g) to the reaction container will __________. A) increase the partial pressure of CO (g) at equilibrium B) decrease the partial pressure of CO2 (g) at equilibrium C) increase the value of the equilibrium constant D) increase the partial pressure of CO2 (g) at equilibrium E) decrease the value of the equilibrium constant

D

Consider the following reaction at equilibrium: C(s) + H2O (g) <--> CO (g) + H2 (g) Which of the following conditions will increase the partial pressure of CO? A) decreasing the partial pressure of H2O (g) B) removing H2O (g) from the system C) decreasing the volume of the reaction vessel D) decreasing the pressure in the reaction vessel E) increasing the amount of carbon in the system

D

HA is a weak acid. Which equilibrium corresponds to the equilibrium constant Kb for A- ? A) HA (aq) + H2O (l) <--> H2A+ (aq) + OH- B) A- (aq) + H3O+ (aq) <--> HA (aq) + H2O (l) C) HA (aq) + OH- (aq) <--> H2O (l) + H+(aq) D) A- (aq) + H2O (l) <--> HA (aq) + OH- (aq) E) A- (aq) + OH- (aq) <--> HOA^2- (aq)

D

If the rate law for the reaction 2A + 3B → products is first order in A and second order in B, then the rate law is rate = ____________. A) k[A]2[B]3 B) k[A]2[B]2 C) k[A]2[B] D) k[A][B]2 E) k[A][B]

D

Of the following substances, an aqueous solution of __________ will form basic solutions. NH4Cl , Cu(NO3)2 , K2CO3 , NaF A) NH4Cl , Cu(NO3)2 B) K2CO3 , NH4Cl C) NaF only D) NaF , K2CO3 E) NH4Cl only

D

The effect of a catalyst on an equilibrium is to __________. A) increase the rate of the forward reaction only B) increase the equilibrium constant so that products are favored C) slow the reverse reaction only D) increase the rate at which equilibrium is achieved without changing the composition of the equilibrium mixture E) shift the equilibrium to the right

D

The equilibrium constant for reaction 1 is K. The equilibrium constant for reaction 2 is __________. (1) SO2 (g) + (1/2) O2 (g) <--> SO3 (g) (2) 2SO3 (g) <--> 2SO2 (g) + O2 (g) A) K^2 B) 2K C) 1/2K D) 1/K^2 E) -K^2

D

The mechanism for formation of the product X is: A + B → C + D (slow) B + D → X (fast) The intermediate reactant in the reaction is __________.

D

The overall order of a reaction is 2. The units of the rate constant for the reaction are __________. A) M/s B) 1/s C) s/M2 D) M-1s-1 E) 1/M

D

The rate of a reaction depends on __________. A) collision frequency B) collision energy C) collision orientation D) all of the above E) none of the above

D

What is the conjugate base of OH-? A) O- B) H2O C) H3O+ D) O2- E) O2

D

Which of the following aqueous solutions has the highest [OH-]? A) a solution with a pH of 3.0 B) a 1 x 10-4 M solution of HNO3 C) a solution with a pOH of 12.0 D) pure water E) a 1 x 10-3 M solution of NH4Cl

D

4) The Ka of acetic acid is . The pH of a buffer prepared by combining 50.0 mL of 1.00 M potassium acetate and 50.0 mL of 1.00 M acetic acid is __________. A) 1.705 B) 0.851 C) 3.406 D) 4.754 E) 2.383

D) 4.754

Which one of the following substances is more likely to dissolve in CCl4? A) CH3CH2OH B) NaCl C) HBr D) CBr4 E) HC

D) CBr4

Which of the following substances is least likely to dissolve in water? A) O⇌CH₃(CH₂)₉CH B) CH₃(CH₂)₈CH₂OH C) HOCH₂CH₂OH D) CCl₄ E) CHCl₃

D) CCl₄ HOCH₂CH₂OH is the most likely to dissolve in water

Which one of the following is most soluble in hexane (C6H14)? A) CH3CH2CH2CH2OH B) CH3OH C) CH3CH2CH2OH D) CH3CH2CH2CH2CH2OH E) CH3CH2OH

D) CH3CH2CH2CH2CH2OH

38) Which of the following ions will act as a weak base in water? A) OH- B) Cl- C) NO3 D) ClO- E) None of the above will act as a weak base in water.

D) ClO

12) The addition of sodium hydroxide and __________ to water produces a buffer solution. A) HCl B) NaC2H3O2 C) NaF D) HC7H5O2 E) NaCl

D) HC7H5O2

52) Of the following, which is the strongest acid? A) HClO B) HCIO3 C) HCIO2 D) HCIO4 E) HIO

D) HCIO4

4) What change will be caused by addition of a small amount of HCl to a solution containing fluoride ions and hydrogen fluoride? A) The concentration of hydronium ions will increase significantly. B) The concentration of fluoride ions will increase as will the concentration of hydronium ions. C) The concentration of hydrogen fluoride will decrease and the concentration of fluoride ions will increase. D) The concentration of fluoride ion will decrease and the concentration of hydrogen fluoride will increase. E) The fluoride ions will precipitate out of solution as its acid salt.

D) The concentration of fluoride ion will decrease and the concentration of hydrogen fluoride will increase.

2) A Br nsted-Lowry base is defined as a substance that __________. A) increases when placed in B) decreases when placed in C) increases when placed in D) acts as a proton acceptor E) acts as a proton donor

D) acts as a proton acceptor

Which of the following liquids will have the lowest freezing point? A) pure H₂O B) aqueous glucose (0.60 m) C) aqueous FeI₃ (0.24 m) D) aqueous KF (0.50 m) E) aqueous sucrose (0.60 m)

D) aqueous KF (0.50 m)

Of the concentration units below, only __________ is temperature dependent. A) mass % B) molality C) ppm D) molarity E) ppb

D) molarity

The ratio of the actual value of a colligative property to the value calculated, assuming the substance to be a non electrolyte, is referred to as: A) vapor pressure lowering B) freezing point depression C) Henry's law D) the van't Hoff factor E) osmotic pressure

D) the van't Hoff factor

The equilibrium-constant expression depends on the __________ of the reaction. A. the quantities of reactants and products initially present B. stoichiometry and mechanism C. mechanism D. stoichiometry E. temperature

D. stoichiometry

Increasing the temperature of a system in dynamic equilibrium favours the endothermic reaction. The system counteracts the change you have made by absorbing the extra heat.

Decreasing the temperature of a system in dynamic equilibrium favors the exothermic reaction. The system counteracts the change you have made by producing more heat.

How does the reaction quotient of a reaction (Q) differ from the equilibrium constant (Keq) of the same reaction? A) Q does not change with temperature. B) Q does not depend on the concentrations or partial pressures of reaction components. C) K does not depend on the concentrations or partial pressures of reaction components. D) Keq does not change with temperature, whereas Q is temperature dependent. E) Q is the same as Keq when a reaction is at equilibrium.

E

How is the reaction quotient used to determine whether a system is at equilibrium? A) The reaction quotient must be satisfied for equilibrium to be achieved. B) At equilibrium, the reaction quotient is undefined. C) The reaction is at equilibrium when Q < Keq. D) The reaction is at equilibrium when Q > Keq . E) The reaction is at equilibrium when Q = Keq.

E

In which of the following reactions would increasing pressure at constant temperature NOT change the concentrations of reactants and products, based on Le Chatelier's principle? A) N2 (g) + 3H2 (g) <--> 2NH3 (g) B) N2O4 (g) <--> 2NO2 (g) C) N2 (g) + 2O2 (g) <--> 2NO2 D) 2N2 (g) + O2 (g) <--> 2N2O (g) E) N2 (g) + O2 (g) <--> 2NO (g)

E

The conjugate acid of HSO4- is A) SO42- B) H+ C) HSO4+ D) HSO3+ E) H2SO4

E

The conjugate base of HSO4- is A) HSO4+ B) H3SO4+ C) OH- D) H2SO4 E) SO42-

E

The data in the table below were obtained for the reaction: A + B --> P exp, [A](M), [B](M), Initial Rate (M/s) 1, 0.273, 0.763, 2.83 2, 0.273, 1.526, 2.83 3, 0.819, 0.763, 25.47 The rate law for this reaction is rate = __________. A) k[A][B] B) k[P] C) k[A]^2 [B] D) k[A]^2 [B]^2 E) k[A]^2

E

The equilibrium expression for Kp for the reaction below is __________. 2O3 (g) <--> 3O2 (g) A) 3PO2 / 2PO3 B) 2PO3 / 3PO2 C) 3PO3 / 2PO2 D) PO3^2 / PO2^2 E) PO2^3 / PO3^2

E

The order of the reaction in B is __________. A) 1 B) 2 C) 3 D) 4 E) 0

E

The primary source of the specificity of enzymes is __________. A) their polarity, which matches that of their specific substrate B) their delocalized electron cloud C) their bonded transition metal, which is specific to the target substrate D) their locations within the cell E) their shape, which relates to the lock-and-key model

E

Under constant conditions, the half-life of a first-order reaction __________. A) is the time necessary for the reactant concentration to drop to half its original value B) is constant C) can be calculated from the reaction rate constant D) does not depend on the initial reactant concentration E) All of the above are correct.

E

What is the conjugate acid of NH3? A) NH3+ B) NH4OH C) NH2+ D) NH3 E) NH4+

E

What is the overall order of the reaction? A) 4 B) 0 C) 1 D) 2 E) 3

E

Which of the following ions will act as a weak base in water? A) HS- B) F- C) NO2- D) ClO- E) All of the above will act as a weak base in water.

E

Which of the following statements is true? A) Q does not change with temperature. B) Keq does not change with temperature, whereas Q is temperature dependent. C) K does not depend on the concentrations or partial pressures of reaction components. D) Q does not depend on the concentrations or partial pressures of reaction components. E) Q is the same as Keq when a reaction is at equilibrium.

E

Which one of the following is a Br0nsted-Lowry acid? A) (CH3)3NH+ B) CH3COOH C) HF D) HNO2 E) all of the above

E

Which one of the following is not a valid expression for the rate of the reaction below? 4NH3 + 7O2 --> 4NO2 + 6H2O A) -1/7 (Δ[O2]/Δt) B) 1/4 (Δ[NO2]/Δt) C) 1/6 (Δ[H2O]/Δt) D) -1/4 Δ[NH3]/Δt E) All of the above are valid expressions of the reaction rate.

E

A 0.100 m solution of which one of the following solutes will have the lowest vapor pressure? A) sucrose B) NaCl C) KClO₄ D) Ca(ClO₄)₂ E) Al(ClO₄)₃

E) Al(ClO₄)₃

39) Which of the following ions will act as a weak base in water? A) HS- B) F- C) NO2- D) ClO E) All of the above will act as a weak base in water.

E) All of the above will act as a weak base in water.

Which one of the following substances would be the least soluble in CCl₄? A) NH3 B) H2O C) C10H22 D) CH3CH2OH E) NaCl

E) NaCl The most soluble in CCl₄ would be C₁₀H₂₂

21) Classify the following compounds as weak acids (W) or strong acids (S): benzoic acid nitric acid acetic acid A) W W W B) S S S C) S W W D) W S S E) W S W

E) W S W

23) Classify the following compounds as weak acids (W) or strong acids (S): nitrous acid hydrochloric acid hydrofluoric acid A) W W W B) S S S C) S W W D) W S S E) W S W

E) W S W

38) Which below best describe(s) the behavior of an amphoteric hydroxide in water? A) With conc. aq. NaOH, its suspension dissolves. B) With conc. aq. HCl, its suspension dissolves. C) With conc. aq. NaOH, its clear solution forms a precipitate. D) With conc. aq. HCl, its clear solution forms a precipitate. E) With both conc. aq. NaOH and conc. aq. HCl, its suspension dissolves.

E) With both conc. aq. NaOH and conc. aq. HCl, its suspension dissolves

Which of the following expressions is the correct equilibrium-constant expression for the following reaction?

E) [CH3OH] / [CO2][H2]2

When two non polar organic liquids are mixed, a solution forms and the enthalpy of solution is quite small. Label the two organic liquids as A (solvent) and B (solute). The formation of solution is favored by: A) the highly negative enthalpy of the solution process B) the equal enthalpy of the solvent and solute C) solvation of the solvent, A D) hydration of solute B E) an increase in disorder, since A-A, B-B, and A-B interactions are similar

E) an increase in disorder, since A-A, B-B, and A-B interactions are similar

Which of the following liquids will have the lowest freezing point? A) pure H2O B) aqueous CoI2 (0.030 m) C) aqueous NaI (0.030 m) D) aqueous glucose (0.050 m) E) aqueous FeI3 (0.030 m)

E) aqueous FeI3 (0.030 m)

3. A reaction energy diagram plots the energy of the system as a function of the ____________________.

Reaction Coordinate

Consider the following reaction at equilibrium: Zn(s) +2H+(aq) <--> Zn2+(aq) + H2(g) Which of the following is true if one adds more Zn(s) to the reaction mixture? A. More H2(g) is produced B. More H+(aq) is consumed C. More Zn+2 goes into solution D. 1,2, and 3 will happen E. None of the above will happen

E. None of the above will happen

How does the reaction quotient of a reaction differ from the equilibrium constant of the same reaction? A. Q does not change with temperature. B. Q does not depend on the concentrations or partial pressures of reaction components. C. K does not depend on the concentrations or partial pressures of reaction components. D. Keq does not change with temperature, whereas Q is temperature dependent. E. Q is the same as Keq when a reaction is at equilibrium.

E. Q is the same as Keq when a reaction is at equilibrium.

Consider the following reaction at equilibrium: 2NH3 (g) N2 (g) + 3H2 (g) Le Chatelier's principle predicts that the moles of H2 in the reaction container will increase with __________. A. some removal of NH3 from the reaction vessel (V and T constant) B. an increase in total pressure by the addition of helium gas (V and T constant) C. addition of some N2 to the reaction vessel (V and T constant) D. a decrease in the total volume of the reaction vessel (T constant) E. a decrease in the total pressure (T constant)

E. a decrease in the total pressure (T constant)

an increase in temperature shifts equilibrium to the right

Endothermic Reaction

an increase in temperature shifts equilibrium to left

Exothermic Reaction

The extent of ionization of a weak electrolyte is increased by adding to the solution a strong electrolyte that has an ion in common with the weak electrolyte.T/F

FALSE

The half-life for a first order rate law depends on the starting concentration. T/F

FALSE

The solubility product of a compound is numerically equal to the product of the concentration of the ions involved in the equilibrium, each multiplied by its coefficient in the equilibrium reaction. T/F

FALSE

Which element is oxidized in the reaction below? Fe^(2+) + H^(+) + Cr2O7^(2-) ---->Fe^(3+) + Cr^(3+) + H2O

Fe

Which substance is the reducing agent in the following reaction? Fe2S3 + 12HNO3 ----> 2Fe(NO3)3 + 3S + 6NO2 + 6H2O

Fe2S3

Why does fluoride treatment render teeth more resistant to decay? a. Fluoride kills the bacteria in the mouth that make the acids that decay teeth. b. Fluoride stimulates production of tooth enamel to replace that lost to decay. c. Fluoride reduces saliva production, keeping teeth drier and thus reducing decay. d. Fluoride converts hydroxyapatite to fluoroapatite that is less reactive with acids. e. Fluoride dissolves plaque, reducing its decaying contact with teeth.

Fluoride converts hydroxyapatite to fluoroapatite that is less reactive with acids.

1) The presence of ions. 2) The presence of a dipole moment. 3) The presence of London dispersion forces.

For example a salt such as magnesium sulfate, MgSO_4, is very soluble in water because the water molecules will solvate the charged magnesium atom and the sulfate molecule very easily.

.0119

Given the following reaction at equilibrium at 300.0 K: NH4HS (s) NH3 (g) + H2S (g) If pNH3 = pH2S = 0.109 atm, Kp = __________.

0.0821

Given the following reaction at equilibrium at 450.0 °C: CaCO3 (s) CaO (s) + CO2 (g) If pCO2 = 0.0135 atm, Kc = __________.

1.90 x 1019

Given the following reaction at equilibrium, if Kc = 1.90 x 1019 at 25.0 °C, Kp = __________.

1.53 x 104

Given the following reaction at equilibrium, if Kc = 6.34 x 105 at 230.0 °C, Kp = __________.

2.31 x 10-2

Given the following reaction at equilibrium, if Kp = 0.990 at 250.0 °C, Kc = __________. PCl5 (g) PCl3 (g) + Cl2 (g)

conjugate acid-base pairs differ only by an

H+

goes up regardless of whether the reaction is exothermic or endothermic

In general, as temperature goes up, reaction rate ________. A) goes up if the reaction is exothermic B) goes up if the reaction is endothermic C) goes up regardless of whether the reaction is exothermic or endothermic D) stays the same regardless of whether the reaction is exothermic or endothermic E) stays the same if the reaction is first order

Chemical, physical

In general, intramolecular forces determine the __________ properties of a substance and intermolecular forces determine its __________ properties.

A

In the Arrhenius equation, k = Ae^-Ea/RT ________ is the frequency factor. A) k B) A C) e D) Ea E) R

activated complex

In the energy profile of a reaction, the species that exists at the maximum on the curve is called the ________. A) product B) activated complex C) activation energy D) enthalpy of reaction E) atomic state

0.020 M BaCl2

In which of the following aqueous solutions would you expect PbCl2to have the lowest solubility?

all of the above

In which of the following reactions would increasing pressure at constant temperature change the concentrations of reactants and products, based on Le Châteliers principle?

Increase Temp then Rate

Increases

Increase k then Temp increases and rate

Increases (generally exponentially)

If a reaction is endothermic, ________ the reaction temperature results in an increase in K.

Increasing

The slope of a line drawn tangent to the concentration-versus-time curve at a specific time =

Instantaneous Rate

produced in one elementary step, consumed in a later elementary step and therefore doesn't appear in overall equation for r x n

Intermediate

Which of the following is true concerning the Haber process?

It is a process used for the synthesis of ammonia.

Which one of the following is true concerning the Haber process?

It is a process used for the synthesis of ammonia.

Using Le Chatelier's Principle: Consider a simple system where A(g)--> B(g) An equilibrium mixture has [A] = 0.500 M and [B] = 1.75 M What is the equilibrium constant?

K = [B]/[A] = 1.75 M/0.500 M = 3.5 Calculate the concentrations of A and B if 0.500 M of A is added: Cpd []i +n New[] delta[] []eq []final A 0.05 0.05 1.0 -x 1.0-x 0.61 B 1.75 0.00 1.75 +x 1.75+x 2.14 𝐾=3.5=((1.75+𝑥)/(1−𝑥)) x = 0.39

Which one of the following statements is true about the equilibrium constant for a reaction if Delta G° for the reaction is negative?

K > 1

A 0.1 M aqueous solution of ____ will have a pH of 7.0 at 25.0 °C.

KCl

The molar solubility of _________ is not affected by the pH of the solution. a. Na3PO4 b. NaF c. KNO3 d. AlCl3 e. MnS

KNO3

The molar solubility of _________ is not affected by the pH of the solution.

KNO3

Which one of the following pairs cannot be mixed together to form a buffer solution? A) C5H5N, C5H5NHCl B) HC2H3O2, NaOH (C2H3O2- = acetate) C) KOH, HI D) NH2CH3, HCl E) NaClO, HNO3

KOH, HI A buffer MUST contain a weak acid-conjugate base pair. The only one of these pairs which CANNOT form a buffer is KOH/HI, since you have a strong acid and a strong base.

The pH of a 0.55 M aqueous solution of HBrO is 4.48. What is the value of Ka for HBrO?

Ka= 2.0 x 10^(-9)

Kb for C5H5N is 1.4 x 10^(-9). What is Ka for C5H5NH+

Ka= 7.1 x 10^(-6)

A 0.035 M solution of ammonia has a pH of 11.33. Calculate Kb for ammonia.

Kb= 1.3 x 10^(-4)

Ka for HCN is 4.9 x 10(-10). What is Kb for CN?

Kb= 2.0 x 10^(-5)

Converting between Kc and Kp: N2(g) + 3H2(g) --><-- 2NH3(g)

Kc = 9.60 at 300 ᵒC, Calculate Kp Kp = Kc (RT)Delta n What is T ? T= 300 + 273 = 573 K What is Delta n ? Delta n = n products - n reactants = 2 - 4 = -2 Kp = 9.6(0.0821 x 573)^-2 = 4.34 x 10^-3

Equilibrium equation of form: aA + bB <---> dD + eE; the equilibrium-constant expression is=

Kc = [D]^d[E]^e/[A]^a[B]^b Kc is the equilibrium constant

If Reaction A + Reaction B = Reaction C, then Kc Reaction C = ________.

Kc Reaction A x Kc Reaction B

A 3.25 L tank was found to contain 0.343 mol O₂, 0.0212 mol So₃, and 0.00419 mol SO₂, when equilibrium was attained. What is the value of Keq for this reaction? 2SO₃₃→2SO₂+O₂

Keq= 4.15 x 10⁻³

Write the equilibrium expression for the following 2CO (g) ↔ C (s) + CO₂ (g)

Keq= [CO₂] / [CO]²

Write the equilibrium expression for the following 4CuO (s) + CH₄ (g) ↔ CO₂ (g) + 4Cu (s) + 2H₂O (g)

Keq= [H₂O]² [CO₂] / [CH₄]

Write the equilibrium expression for the following NH₄HS (s) ↔ NH₃ (g) + H₂S (g)

Keq= [NH₃] [H₂S]

5.44

Kp = 0.0198 at 721 K for the reaction 2HI (g) H2 (g) + I2 (g) In a particular experiment, the partial pressures of H2 and I2 at equilibrium are 0.836 and 0.701 atm, respectively. The partial pressure of HI is __________ atm.

How is Kp related to Kc at a given temperature ?

Kp is less than Kc: Kp = Kc(RT) raised to the delta n delta n = 4-5 = -1 so Kp < Kc

Consider Endothermic reaction: PCl5 <--> PCl3 + Cl2 At a certain temp., the equilibrium mixture contains 1.5atm PCl5, 0.10atm PCl3, and 7.50atm Cl2. What is equilibrium constant, Kp, for reaction?

Kp= (PCl₃)(PCl₂) / (PCl₅) Kp= (0.10)(7.50) / (1.5) Kp= 0.50

A reaction vessel is charged with hydrogen iodide, which partially decomposes to molecular hydrogen and iodine : 2HI (g)↔ H₂ (g) + I₂ (g) when the system comes to equilibrium at 425 °C, Pressure of HI= 0.708 atm, and pressure of H₂= 0.0962 atm. Calculate the value of Kp

Kp= 1.84 x 10⁻²

If a system at equilibrium is disturbed, the equilibrium will shift to minimize the disturbing influence.

Le Chateliers Principle: If a reactant or product is added to a system at equilibrium, the equilibrium will shift to consume the added substance.

...

List the common particles and their symbols used in descriptions of radioactive decay and nuclear transformations.

When substrate molecules bind very specifically to the active site of the enzyme, after which they can undergo r x n is called the

Lock-and-Key model

Liquids that mix in all proportions are --------

Miscible Hydrogen-Bonding interactions between solute and solvent play an important role in determining solubility; Ex: Ethanol and water, whose molecules form hydrogen bonds with each other, are miscible.

Moles of solute per liter of soln. ---

Molarity, M If density of solution is known, Molarity can be converted to these other concentration units

5. When the equilibrium constant K is << 1, the reaction is said to be ________________________.

Reaction Favored

Rank the following substances in order from most soluble in water to least soluble in water. methane: CH4, hexanol: C6H13OH, table salt: NaCl, propane: C3H8

Most Soluble to Least Soluble: Salt > Hexanol > Propane > Methane

Of the following equilibria, only __________ will shift to the right in response to a decrease in volume.

N2 (g) + 3 H2 (g) = 2 NH3 (g)

The addition of hydrochloric acid and ________ to water produces a buffer solution. HC6H5O NaOH NH3 HNO3 NaNO3

NH3

Of the following substances, an aqueous solution of _____ will form basic solutions.

NaF, K2CO3

AgCl is almost insoluble in water. Would you expect there to be significant increase in entropy when 10.0 g of AgCl is added to 1L of water?

No. The AgCl will not dissolve to a significant extent so there will be almost no increase in entropy.

It is important to note carefully what is happening in any given situation. Consider: Ni (s) + HCl (aq) ---> NiCl2(aq) + H2(g) Is this a solution process?

No. This is a chemical reaction that leads to a dissolved substance.

Which of the following molecules has hydrogen bonding as its only intermolecular force?

None, all of these exhibit dispersion forces.

In which of the following reactions would increasing pressure at constant temperature not change the concentrations of reactants and products, based on Le Chetelier's principle?

N₂ (g) +2O₂ (g) ↔ 2NO₂ (g) noble gases

What is the conjugate base of OH-?

O2- (superscript 2 not subscript)

none of the above

The addition of sodium hydroxide and ________ to water produces a buffer solution. A) HCl B) NaC2H3O2 C) NaF D) NH3 E) none of the above

2. The movement of solvent toward a solution with a higher solute concentration is called ______________.

Osmosis

Movement of solvent molecules through a sempipermeable membrane from a less concentrated to a more concentrated solution

Osmosis (This net movement of solvent generates an osmotic pressure, can be measured in atm.)The osmotic pressure of a solution is proportional to the solution molarity: pie = MRT

Which substance in the reaction below either appears or disappears the fastest? 4NH₃ +7O₂ → 4NO₂ + 6H₂O

O₂

Oxidation numbers P₂O₅

P= 5+ O= 2-

66.7

Phosphorous trichloride and phosphorous pentachloride equilibrate in the presence of molecular chlorine according to the reaction: PCl3 (g) + Cl2 (g) PCl5 (g) An equilibrium mixture at 450 K contains PPCl3 = 0.124 atm, PCl2 = 0.157 atm, and PPCl5 = 1.30 atm. What is the value of Kp at this temperature?

Colligative

Physical properties of a solution that depend on the quantity of the solute particles present, but not the kind or identity of the particles, are termed __________ properties.

The equilibrium expression for Kp for the reaction below is __________. 2 O3 (g) = 3 O2 (g)

Po2^3 --------- Po3^2

If the value for the equilibrium constant is much greater than 1, then the equilibrium mixture contains mostly ______.

Products

The equilibrium constant for the gas phase reaction 2SO₂ (g) + O₂ (g) ↔ 2SO₃ (g) is Keq = 2.80 x 10² at 30° C. At equilibrium _____.

Products predominate

How is the reaction quotient used to determine whether a system is at equilibrium

Q = Keq

For this reaction : CO(g) + H₂O (g) ↔ H₂ (g) + CO₂ (g) Keq= 5.10 If [CO] + 0.15, [H₂O] = 0.25 M, [H₂] =0.42 M and [CO₂] = 0.37 M. What is the value of Q? Has the reaction reached equilibrium? If not, in which direction will it proceed?

Qeq= 4.1 Qeq < Keq The reaction has not reached equilibrium and will shift to the right (products )

For the reaction : H₂ (g) + I₂ (g) ↔ 2HI (g) If [H₂] = 0.195 M, [I₂] = 0.172, and [HI] = 1.30 M. What is the value of Q? Has the reaction reached equilibrium? If not, in which direction will it proceed?

Qeq= 50.4 Qeq = Keq The reaction has reached equilibrium

If a rate law is second order (reactant), doubling the reactant _________ the reaction rate

Quadruples

k = m & n = The sum of the reaction orders give the =

Rate Constant Reaction Orders for reactants Overall Reaction Order

When mechanism has several elementary steps, the overall rate is limited by the slowest elementary step =

Rate-determining step; A fast elementary step that follows the rate-determing step will have no effect on the rate law of the r x n

The equilibrium constant for the gas phase reaction N₂ (g) +3H₂ (g) ↔ 2NH₃ (g) is Keq = 4.34 x 10⁻³ at 300°C. At equilibrium ______.

Reactants predominate

The equilibrium constant for the gas phase reaction N₂ (g) +O₂ (g) 2NO ↔ (g) is Keq = 4.20 x 10⁻³¹ at 30° C. At equilibrium _________.

Reactants predominate

Details the individual step that occur in course of r x n =

Reaction Mechanism Each of these steps are Elementary reactions with a well-defined rate law that depends on # of molecules (molecularity) of the step. Defined as either unimolecular, bimolecular, or termolecular, depending on whether 1, 2, or 3 reactant molecules are involved.

The number obtained by substitution starting reactant and product concentrations into an equilibrium constant expression is known as the ________.

Reaction quotient

Arrhenius

Reaction rate data showing temperature dependence obey an equation devised by ________.

collision model

Reaction rates are affected by reactant concentrations and temperature. This is accounted for by the ________.

The equilibrium constant expression for a reaction written in one direction is the ________ of the one for the reaction written in the reverse direction.

Reciprocal

The conjugate base of HSO4- is ____________.

SO4 2- (superscript 2 -)

Soln. in equilibrium with undissolved solute, the two processes occur at equal rates, giving a --------- soln.

Saturated Soln.

Which one of the following should have the lowest boiling point?

SiH4

------ and ------- don't expand to fill their containers and are not readily compressible

Solids and Liquids

Pure ________ and pure ______ are excluded from equilibriul constant expressions.

Solids, liquids

1. The maximum amount of one substance that can dissolve in another substance is referred to as its ______________.

Solubility

dissolved substance If both in same phase; Component in greatest amount is the solvent

Solute

The attractive interaction of solvent molecules with solute is called -----

Solvation

Substance whose phase is maintained when soln made.

Solvent

NaCl(s) + H2O(l) --> NaCl(aq) Solvent = Liquid = Solute =

Solvent = Liquid H2O Liquid = NaCl (aq) Solute = NaCl (s)

What is a weak base?

Something that does not completely associate in a solution

You dissolve 0.144 g of oil of cloves (C10H12O2, molecular mass = 164.2) in 10.0 g benzene. The normal boiling point of benzene is 80.1 C. If the Kb of benzene is 2.53 C/m, what is the boiling point of the solution?

Step 1: Decide whether oil of cloves is ionic or molecular? Molecular Step 2: Calculate the molality of oil of cloves: (0.144 g)(1 mol/164.2 g) = 8.77 x 10-4 mol m = mol/kg solvent = 8.77 x 10-4 mol / 0.01 kg m = 8.77 x 10-2 Step 3: Calculate the change in boiling point: ΔTb = Kb m ΔTb = 2.53 degrees C/m (8.77 x 10-2 m) = 0.222 degrees C Step 4: Find the new boiling point : T = Tb + ΔTb = 80.10 + 0.222 = 80.32 degrees C

The presence of London dispersion forces

Substances that lack ions or a dipole moment are generally hydrophobic. However, when comparing two nonpolar gases, the one with the greater London forces will generally be the more hydrophilic of the two. In general, London forces become larger as the size of the atom or molecule increases. So O2 (MW=32) is more soluble in water than N2 (MW = 28).

The specific reactant molecules involved in an enzymatic r x n are

Substrates

When solute concentration is greater than the equilibrium concentration value, the soln. is ---

Supersaturated

Arrhenius

Swedish chemist and chemist noted for his theory of chemical dissociation (1859-1927)

For any buffer system, the buffer capacity depends on the amount of acid and base from which the buffer is made. T/F

TRUE

The rate limiting step in a reaction is the slowest step in the reaction sequence. T/F

TRUE

The rate of a second order reaction can depend on the concentrations of more than one reactant. T/F

TRUE

You have a solution of NaOCl (74.5 g/mol) labeled 3.62 mass % in water. What is the mole fraction of NaOCl?

Take 100 g of the solution = 3.62 g NaOCl and 96.38 g of water Calculate the moles of each; NaOCl = 3.62 g/74.5 g/mol = 0.0486 mol H2O = 96.38 g /18 g/mol = 5.35 mol Calculate the mol fraction: XNaOCl = 0.0486/ (0.0486 + 5.35) = 8.95 x 10-3

Value of equilibrium constant changes with :

Temperature

pH = pKa + log [base/acid]

The Henderson-Hasselbalch equation is ________. A) [H+] = Ka + [base/acid] B) pH = pKa - log [base/acid] C) pH = pKa + log [base/acid] D) pH = pKa + log [acid/base] E) pH = log [acid/base]

pH = pKa + log [base] [acid]

The Henderson-Hasselbalch equation is __________.

4.201

The Ka of benzoic acid is 6.30 × 10-5. The pH of a buffer prepared by combining 50.0 mL of 1.00 M potassium benzoate and 50.0 mL of 1.00 M benzoic acid is __________.

NH3

The addition of hydrochloric acid and ________ to water produces a buffer solution. A) HC6H5O B) NaOH C) NH3 D) HNO3 E) NaNO3

NaOH

The addition of hydrofluoric acid and ________ to water produces a buffer solution. A) HCl B) NaNO3 C) NaCl D) NaOH E) NaBr

NaF

The addition of hydrofluoric acid and __________ to water produces a buffer solution.

What change will be caused by addition of a small amount of HCl to a solution containing fluoride ions and hydrogen fluoride? A)The fluoride ions will precipitate out of solution as its acid salt. B) The concentration of hydrogen fluoride will decrease and the concentration of fluoride ions will increase. C) The concentration of fluoride ion will decrease and the concentration of hydrogen fluoride will increase. D) The concentration of fluoride ions will increase as will the concentration of hydronium ions. E) The concentration of hydronium ions will increase significantly.

The concentration of fluoride ion will decrease and the concentration of hydrogen fluoride will increase. Since hydrochloric acid is a strong acid, many hydronium ion are added. To remove them the equilibrium shifts to the left with a decrease in the fluoride ion concentration and an increase in the HF concentration.

2

The data in the table below were obtained for the reaction: (see photo) A + B → P The order of the reaction in A is ________. A) 1 B) 2 C) 3 D) 4 E) 0

0

The data in the table below were obtained for the reaction: (see photo) A + B → P The order of the reaction in B is ________. A) 1 B) 2 C) 3 D) 4 E) 0

2

The data in the table below were obtained for the reaction: (see photo) A + B → P The overall order of the reaction is ________. A) 1 B) 2 C) 3 D) 4 E) 0

230

The data in the table below were obtained for the reaction: (see photo) 2 ClO₂ (aq) + 2 OH⁻ (aq) → ClO₃⁻ (aq) + ClO₂⁻ (aq) + H₂O (1) What is the magnitude of the rate constant for the reaction? A) 1.15 × 10⁴ B) 4.6 C) 230 D) 115 E) 713

2

The data in the table below were obtained for the reaction: (see photo) 2 ClO₂ (aq) + 2 OH⁻ (aq) → ClO₃⁻ (aq) + ClO₂⁻ (aq) + H₂O (1) What is the order of the reaction with respect to ClO₂? A) 1 B) 0 C) 2 D) 3 E) 4

3

The data in the table below were obtained for the reaction: (see photo) 2 ClO₂ (aq) + 2 OH⁻ (aq) → ClO₃⁻ (aq) + ClO₂⁻ (aq) + H₂O (1) What is the overall order of the reaction? A) 4 B) 0 C) 1 D) 2 E) 3

38.0

The data in the table below were obtained for the reaction: A + B → P (see photo) The magnitude of the rate constant is ________. A) 38.0 B) 0.278 C) 13.2 D) 42.0 E) 2.21

k[A]²

The data in the table below were obtained for the reaction: A + B → P (see photo) The rate law for this reaction is rate = ________. A) k[A][B] B) k[P] C) k[A]²[B] D) k[A]²[B]² E) k[A]²

Calculate the molarity of a 25.4% (by mass) aqueous solution of phosphoric acid (H3PO4).

The density of the solution is needed to solve the problem

polarizability

The ease with which the charge distribution in a molecule can be distorted by an external electrical field is called the __________.

0.0330

The equilibrium constant (Kp) for the interconversion of PCl5 and PCl3 is 0.0121: PCl5 (g) PCl3 (g) + Cl2 (g) A vessel is charged with PCl5, giving an initial pressure of 0.123 atm. At equilibrium, the partial pressure of PCl3 is __________ atm.

reactants predominate

The equilibrium constant for the gas phase reaction N2 (g) + 3H2 (g) 2NH3 (g) is Keq = 4.34 × 10-3 at 300 °C. At equilibrium, __________.

PCO2 PH2O 2 PCH4

The expression for Kp for the reaction below is __________. 4CuO (s) + CH4 (g) CO2 (g) + 4Cu (s) + 2H2O (g)

second

The kinetics of the reaction below were studied and it was determined that the reaction rate increased by a factor of 9 when the concentration of B was tripled. The reaction is ________ order in B. A + B → P A) zero B) first C) second D) third E) one-half

Charles' Law

The law that states that for a fixed amount of gas at a constant pressure, the volume of the gas increases as the temperature of the gas increases and the volume of the gas decreases as the temperature of the gas decreases. (V₁/T₁=V₂/T₂) (V=constant x T or V/T = constant)

2.69

The most likely van't Hoff factor for an 0.01 m CaI2 solution is __________.

Partial Pressure

The pressure contribution of single gas in a container holding a mixture of gases, as given by the equation Pa = P(total) * Xa. Where Xa is the mole fraction of gas A and P(total) is the total pressure of the mixture.

carbonic acid, bicarbonate

The primary buffer system that controls the pH of the blood is the __________ buffer system.

L mol⁻¹ s⁻¹

The rate law of a reaction is rate = k[D][X]. The units of the rate constant are ________. A) mol L⁻¹ s⁻¹ B) L mol⁻¹ s⁻¹ C) mol2 L⁻² s⁻¹ D) mol L⁻¹ s⁻² E) L² mol⁻² s⁻¹

all of the above

The rate of a reaction depends on ________. A) collision frequency B) collision energy C) collision orientation D) all of the above E) none of the above

How is the reaction quotient used to determine whether a system is at equilibrium?

The reaction is at equilibrium when Q = Keq

At 400 K, the equilibrium constant for the reaction Br2 (g) + Cl2 (g) 2BrCl (g) is Kp = 7.0. A closed vessel at 400 K is charged with 1.00 atm of Br2 (g), 1.00 atm of Cl2 (g), and 2.00 atm of BrCl (g). Use Q to determine which of the statements below is true

The reaction will go to completionsince there are equal amounts of Br2 andCl2

Which of the following compounds has the highest pKa? a. SiH4 b. H2S c. PH3 d. HCl

a

The concentration of fluoride ion will decrease and the concentration of hydrogen fluoride will increase.

What change will be caused by addition of a small amount of HCl to a solution containing fluoride ions and hydrogen fluoride? A) The concentration of hydronium ions will increase significantly. B) The concentration of fluoride ions will increase as will the concentration of hydronium ions. C) The concentration of hydrogen fluoride will decrease and the concentration of fluoride ions will increase. D) The concentration of fluoride ion will decrease and the concentration of hydrogen fluoride will increase. E) The fluoride ions will precipitate out of solution as its acid salt.

x

Which energy difference in the energy profile below corresponds to the activation energy for the forward reaction? (see photo) A) x B) y C) x + y D) x - y E) y - x

0.25 m sucrose

Which of the following aqueous solutions will have the highest boiling point?

sodium acetate or sodium hydroxide

Which of the following could be added to a solution of acetic acid to prepare a buffer? A) sodium acetate only B) sodium acetate or sodium hydroxide C) nitric acid only D) hydrofluoric acid or nitric acid E) sodium hydroxide only

sodium hydroxide

Which of the following could be added to a solution of acetic acid to prepare a buffer? A) sodium hydroxide B) hydrochloric acid C) nitric acid D) more acetic acid E) None of the above can be added to an acetic acid solution to prepare a buffer.

hydrochloric acid

Which of the following could be added to a solution of potassium fluoride to prepare a buffer? A) sodium hydroxide B) potassium acetate C) hydrochloric acid D) sodium fluoride E) ammonia

C) [CH3OH] [CO2][H2]2

Which of the following expressions is the correct equilibrium-constant expression for the following reaction? CO2 (g) + 2H2 (g) CH3OH (g)

PH3

Which one of the following exhibits dipole-dipole attraction between molecules?

CH3OH

Which one of the following is most soluble in water?

RbOH, HBr

Which one of the following pairs cannot be mixed together to form a buffer solution?

KOH, HI

Which one of the following pairs cannot be mixed together to form a buffer solution? A) C5H5N, C5H5NHCl B) HC2H3O2, NaOH (C2H3O2- = acetate) C) KOH, HI D) NH2CH3, HCl E) NaClO, HNO3

NaCl, HCl

Which one of the following pairs cannot be mixed together to form a buffer solution? A) HONH2, HONH3Cl B) NaCl, HCl C) RbOH, HF D) KOH, HNO2 E) H2SO3, KHSO3

NaC2H3O2, HCl (C2H3O2- = acetate)

Which one of the following pairs cannot be mixed together to form a buffer solution? A) NH3, NH4Cl B) NaC2H3O2, HCl (C2H3O2- = acetate) C) RbOH, HBr D) KOH, HF E) H3PO4, KH2PO4

SiH4

Which one of the following should have the lowest boiling point?

CCl4

Which one of the following substances is more likely to dissolve in benzene (C6H6)?

Can CH3OH hydrogen bond to water?

Yes

Will an increase in temperature favor the decomposition of NH4HS?

Yes

Can CH3CH2CH2CH2CH2CH2OH hydrogen bond to water?

Yes.

When you dissolve salt in water, do you expect to see an increase in entropy?

Yes. the Na+ and Cl- ions will no longer be in the regular crystalline lattice but spread out throughout the water.

Overall reaction order is 0 =

Zero Order Reaction Rate = k if the reaction order is zero.

Galvanized iron is coated with

Zinc

The integrated rate law for a first-order reaction is:

[A] = [A]_0e^-kt

For the reaction aA +bB → cC +dD, the rate law is _________.

[A]^a[B]^b

Which of the following expressions is the correct equilibrium-constant expression for the following reaction? NOTE: There was an error in the imagery used with this question. In ALL of the answers below, CO2 should be read as CO. CO (g) + 2 H2 (g) = CH3OH (g)

[CH3OH] ------------------ [CO2][H2]^2

acidic solution

[H30+]>[OH-]; and [H30+]>1.0X10^-7M and [OH-]< 1.0X10^-7M at 25 Celsius

Which of the following expressions is the correct equilibrium constant expression for the reaction below? HF (aq) + H₂O (l) ↔ H₃O⁺ (aq) + F⁻ (aq)

[H₃O⁺][F⁻]/[HF]

Which of the following expressions is the correct equilibrium-constant expression for the reaction below? (NH4)2 Se (s) = 2 NH3 (g) + H2Se (g)

[NH3]^2[H2Se]

The equilibrium expression for Kp for the reaction below is what? N₂ (g) + O₂ (g) ↔ 2NO (g)

[NO]²/[N₂][O₂]

Which of the following expressions is the correct equilibrium constant expression for the equilibrium between dinotrogen tetraoxide and nitrogen dioxide?

[NO₂]²/[N₂O₄]

An aqeuous solution contains 0.050 M of CH3NH2. What is the concentration of hydroxide ion in the solution in Molarity. Kb for CH₃NH₂ is 4.4 x 10^(-4)

[OH^-]= 4.7 x 10⁻³

How many stereoisomers of 2,3-dimethylbutane, (CH3)2CHCH(CH3)2, exist? a. 1 b. 2 c. 3 d. 4

a

How many stereoisomers of 2,4-dimethylpentane, (CH3)2CHCH2CH(CH3)2, exist? a. 1 b. 2 c. 3 d. 4

a

What is the approximate pKa value of HCl? a. −7 b. 5 c. 16 d. 51

a

Which of the following anions is the strongest base? a. NH2− b. NH3 c. CH3CH=N− d. CH3C≡N

a

Of the following, __________ will lower the activation energy for a reaction.

adding a catalyst for the reaction

The binding of molecules to the surface of a catalyst is referred to as ________.

adsorption

Metal oxides and hydroxides that are relatively insoluble in neutral water, but are soluble in both strongly acidic and strongly basic solutions are said to be __________.

amphoteric

Steel is

an allow of iron.

Consider the following reaction at equilibrium: 2CO₂ (g) ↔ 2CO (g) +O₂ (g) delta H° = -514 kj Le Chatelier's principle predicts that the equilibrium partial pressure of CO (g) can be maximized by carrying out the reaction ________.

at low temperature and low pressure

equivalence point

at the equivalence point and actual number of moles of NaOH and HCl have reacted, leaving only a solution of their salt. The pH of the solution is 7.0 because the cation of a strong base and the anion of the strong acid are neither acids nor bases and, therefore, have no appreciable effect on pH. AMOUNT OF ACID EQUALS AMOUNT OF BASE

How many stereoisomers of 4-chloro-2-methylpentane (CH3)2CHCH2CHClCH3, exist? a. 1 b. 2 c. 3 d. 4

b

Under which of the following conditions will a reaction be spontaneous when ΔH° > 0? a. TΔS° = 0 b. −TΔS° > ΔH° c. TΔS° < 0° d. ΔG° = 0

b

Which of the following compounds has the lowest pKa? a. H2O b. HBr c. NH3 d. CH4

b

Which of the following compounds is the strongest acid? a. CH3CH2CH2COOH b. CH3CH2CHClCOOH c. CH3CHClCH2COOH d. ClCH2CH2CH2COOH

b

Which of the following compounds is the strongest acid? a. CH3COOH b. ClCH2COOH c. CH3CH2OH d. ClCH2CH2OH

b

Which of the following compounds is the strongest acid? a. CH3COOH b. FCH2COOH c. ClCH2COOH d. BrCH2COOH

b

Which of the following concepts can be used to rationalize the observation that acetic acid is a stronger acid than methanol? a. electronegativity b. resonance c. valence shell electron pair repulsion theory d. Pauli exclusion principle

b

Which of the following is a Lewis acid but not a Brønsted-Lowry acid? a. CH3COOH b. AlCl3 c. H2O d. CH3OH

b

Which of the following is a feature of a Brønsted-Lowry base? a. proton donor b. proton acceptor c. electron pair donor d. electron pair acceptor

b

Which of the following is the correct order of decreasing basicity (stronger base > weaker base)? a. NH3 > MeNH2 > H2O > HF b. MeNH2 > NH3 > MeOH > CH4 c. NH3 > Me3N > H2O > MeOH d. CH3COONa > NaOH > NaOMe > NaNMe2

b

Which of the following is the definition of a meso compound? a. A molecule with stereocenter centers which is chiral b. A molecule with stereocenter centers which is not chiral c. A diastereomer with no stereocenter centers d. A chiral compound with more than one stereocenter center

b

Which of the following is the definition of a pair of enantiomers? a. A pair of structures that are superposable mirror images of one another b. A pair of stereoisomers that are non-superposable mirror images of one another c. A pair of stereoisomers that are not mirror images of one another d. A pair of stereoisomers that have equal specific rotations

b

Which of the following statements is not true? a. The position of the equilibrium for an exergonic reaction favors products b. The products of an exergonic reaction have a higher Gibbs free energy than the reactants. c. The equilibrium constant of a reaction for which ΔG° = 0 is 1. d. ΔG° = ΔH° − TΔS°

b

Which of the following statements regarding optical rotation is not true? a. All (+) enantiomers are dextrorotatory. b. All R enantiomers are dextrorotatory. c. All (−) enantiomers rotate plane-polarized light in a counterclockwise direction. d. All (+) and (−) enantiomers rotate plane-polarized light in opposite directions.

b

Which of the following substituents has the highest priority according to the Cahn-Ingold-Prelog system used in assigning R and S configurations? a. −NH2 b. −NHCH3 c. −CH2NH2 d. −CH2NHCH3

b

Which of the following is the definition of a pair of diastereomers? a. A pair of structures that are superposable mirror images of one another b. A pair of stereoisomers that are non-superposable mirror images of one another c. A pair of stereoisomers that are not mirror images of one another d. A pair of stereoisomers that have equal specific rotations

c

Which of the following is the strongest acid? a. CH3CH3 b. CH3NH2 c. CH3OH d. CH3F

c

Which of the following statements is true? a. All mirror images are enantiomers b. All molecules that have stereocenter centers are chiral c. Isomers that are not superposable on their mirror images are enantiomers d. Superposable structural isomers are enantiomers

c

Which of the following terms describes the reactivity of boron tribromide, BBr3? a. Brønsted-Lowry acid and Lewis acid b. Brønsted-Lowry base and Lewis base c. Lewis acid and not a Brønsted-Lowry acid d. Lewis base and not a Brønsted-Lowry base

c

Which of the following substance is most likely to form an electrolyte when dissolved in water? a. C₁₂H₂₂O₁₁ (table sugar) b. vegetable oil c. CaCl₂ d. C₂H₅OH (alcohol)

c (CaCl₂ - ionic compound)

The small black dots on the outer circles in a diagram of an atom most likely represent: a. atoms b. molecules c. electrons d. chemical bonds

c (electrons)

Which of the following classes of substances would be LEAST soluble in water? a. ionic compounds b. polar compounds c. nonpolar compounds d. salts

c (nonpolar compounds)

The Keq for the equilibrium below is 5.4 × 1013 at 480.0 °C. What is the value of Keq at this temperature for the following reaction?

c 1.4 x 10^-7

What is the concentration of hydroxide ions in a solution at 25.0 C with pH = 4.282? a. 4.28 b. 9.72 c. 1.91 x 10^(-10) d. 5.22 x 10^(-5)

c. 1.91 x 10^(-10)

An aqueous solution contains 0.100 NaOH. What is the pH of the solution? a. 0.100 b. 1.00 c. 13.00 d. 8.00

c. 13.00

A Bronsted-Lowry base is defined as a substance that a. increases (H+) when placed in H2O b. Increase (OH-) when placed in H2O c. Acts as a proton acceptor in any system d. acts as a proton donor in any system

c. Acts as a proton acceptor in any system

Which of the following reactions is a redox reaction a. K₂CrO₄ + BaCl₂ → BaCrO₄ + 2KCl b. Pb ₂⁺² + 2Br⁻ →2PbBr c. Cu + S → CuS a. A only n. B only c. C only d. A and C e. B and C

c. C only

In the reaction 2Ca + O₂ → 2CaO a. O₂ b. O⁻² c. Ca d. Ca⁺²

c. Ca

Nitric Acid is a strong acid. This means a. Aqeous solutions of HNO3 contain equal concentration of H+ and OH- b. HNO3 does not disassociate at all when it is dissolved in water c. HNO3 dissociates completely to H+ and NO3- when it dissolves in water d. HNO3 cannot be neutralized by a weak base

c. HNO3 dissociates completely to H+ and NO3- when it dissolves in water

Which salt when dissolved up in water will have an acidic pH? a. K2CO3 b. NaNO3 c. NH4Cl d. NaF

c. NH4Cl

The equilibrium constant for a reaction can be calculated by a. multiplying the concentration of products to the concentration of reactants b. dividing the concentration of reactants by the concentration of products c. dividing the concentration of products by the concentration of reactants d. using the concentration of the products only

c. dividing the concentration of products by the concentration of reactants

If Q equals Keq, the reaction a. proceeds to the right b. proceeds to the left c. has reached equilibrium d. has come to completion

c. has reached equilibrium

The equilibrium constant for a reaction a. changes with different concentrations b. remains the same with different concentrations c. is a measure of the extent which a reaction proceeds to completion d. is a measure of the reverse reaction

c. is a measure of the extent which a reaction proceeds to completion or d. is a measure of the reverse i don't know

An average reaction rate:

calculated as the change in the concentration of reactants or products over a period of time in the course of the reaction.

The concentrationof reactants or products at any time during the reaction ____ calculated from the integrated rate law.

can be

The rate of a second order reaction ________ on the concentrations of more than one reactant

can depend

The instantaneous rate of a reaction ______ be read directly from the graph of molarity versus time at any point on the graph

cannot

The primary buffer system that controls the pH of the blood is the __________ buffer system. a. carbon dioxide, carbonate b. carbonate, bicarbonate c. carbonic acid, carbon dioxide d. carbonate, carbonic acid e. carbonic acid, bicarbonate

carbonic acid, bicarbonate

how does the presencec of a catalyst affect reaction rates?

catalysists affect the kinds of collisions that occur between reactants (affect the mechanism of the reaction). they increase reaction rates without being used up themselves

According to the Arrhenius concept, an acid is a substance that ____.

causes an increase in the concentration of H+ in aqueous solutions

According to the Arrhenius concept, an acid is a substance that __________.

causes an increase in the concentration of H+ in aqueous solutions

Which of the following is not an alloy?

ceramic

how does reactant concentration affect reaction rates?

chemical reaction rate will increase if the amount of reactant increaes becuase there are more reactant molecules colliding more frequently

A solution is prepared by dissolving 0.23 mol of chloroacetic acid and 0.27 mol of sodium chloroacetate in water sufficient to yield 1.00 L of solution.The addition of 0.05 mol of NaOH to this buffer solution causes the pH to increase slightly. The pH does not increase drastically because the NaOH reacts with the ________ present in the buffer solution. The Ka of chloroacetic acid is 1.4 ⋅ 10^-3. A) chloroacetate B) H3O+ C) H2O D) chloroacetic acid E) This is a buffer solution: the pH does not change upon addition of acid or base.

chloroacetic acid

A gas is __________ and assumes __________ of its container whereas a liquid is __________ and assumes __________ of its container.

compressible, the volume and shape, not compressible, the shape of a portion

Natural rubber is too soft and chemically reactive for practical applications. Vulcanization of natural rubber entails __________.

crosslinking reactive polymer chains with sulfur atoms

Which of the following compounds has the highest pKa? a. NH3 b. H2O c. HCl d. CH4

d

Which of the following compounds has the lowest pKa? a. H2O b. H2S c. H2Se d. H2Te

d

Which of the following compounds is the strongest acid? a. CH3OCH3 b. CH3CH2OH c. CH3CHO d. CH3CO2H

d

Which of the following compounds is the strongest acid? a. CH4 b. CH3CH3 c. H2C=CH2 d. HC≡CH

d

Which of the following is a feature of a Lewis acid? a. proton donor b. proton acceptor c. electron pair donor d. electron pair acceptor

d

Which of the following is easiest to deprotonate? a. CH4 b. CH3CH3 c. CH2=CH2 d. HC≡CH

d

Which of the following is the best definition of a pair of atropisomers? a. A pair of enantiomers which do not interconvert. b. A pair of enantiomers which lack chiral centers. c. A pair of enantiomeric structures which lack chiral centers and interconvert by rotation around carbon-carbon single bonds. d. A pair of enantiomers which lack chiral centers and do not interconvert because of hindered rotation around carbon-carbon single bonds.

d

Which of the following is the strongest acid? a. CH3NH2 b. CH3PH2 c. CH3OH d. CH3SH

d

Which of the following is the strongest acid? a. CH3OH b. CH3CHO c. CH3COCH3 d. CH3COOH

d

Which of the following statements is not true regarding pairs of enantiomers? a. They have identical melting points b. They have identical boiling points. c. They rotate plane polarized light in opposite directions d. They react at identical rates with chiral reagents

d

If an atom were discovered with an average atomic mass of 32 and an atomic number of 15, how many neutrons would it have in an average atom? a. 32 b. 15 c. 47 d. 17

d (17)

Which of the following substances would probably have a pH of 3 or less? a. NaOH b. tap water c. egg white d. H₂SO₄

d (H₂SO₄)

If there were 8 neutrons in the nucleus of this diagram it would be a different: a. molecule b. element c. atom d. isotope

d (isotope)

An uncharged atom with seven protons is a(n) _ atom. a. hydrogen b. carbon c. oxygen d. nitrogen

d (nitrogen)

An ionic bond is formed as the result of: a. the sharing of electrons between two or more atoms b. a release of energy as atoms bond c. a combination of electrons and protons rotating around two or more atoms d. the transfer of electrons from one atom to another

d (the transfer of electrons from one atom to another)

What is the concentration of hydronium ions in a solution at 25.0 C with pH=4.282? a. 4.28 b. 9.71 c. 1.92 x 10^(-10) d. 5.22 x 10(-5)

d. 5.22 x 10(-5)

Which salt when dissolved up in water will have a basic pH? a. NH4CLO4 b.KBr c. NaCl d. Na2SO3

d. Na2SO3

Which change will increase the production of water vapor in this reaction : 2H₂S + 3O₂ ↔2H₂O + 2SO₂ a. adding SO₂ b. removing H₂S c. removing O₂ d. Removing SO₂

d. Removing SO₂

The enthalpy of solution for a solid with approximately equal \Delta H values for each of the steps involved in the solution formation process is __________. a. very exothermic b. slightly exothermic c. very endothermic d. slightly endothermic

d. Slightly Endothermic The dissolution of many salts, such as table salt, is slightly endothermic. The process of dissolving table salt, NaCl, in water has an enthalpy value of Delta H_soln = +4 kJ/mol. Therefore the temperature of the water will decrease slightly when the salt is added.

Chemical equilibrium can be distributed by which of the following a. concentration of reactants and products b. temperature c. pressure d. all of the above

d. all of the above

increasing the pressure on an equilibrium system will a. affect only the gases b. shift the equilibrium position c. cause the reaction to go toward the side that produces fewer molecules of gas d. all of the above

d. all of the above

A substance that can act as either an acid or a base is described as a. neutral b. ambidextrous c. conjugate d. amphoteric

d. amphoteric

The law of mass action states that the relative concentration of reactants and products at equilibrium can be expressed in terms of a. morality b. mass c. temperature. d. an equilibrium constant

d. an equilibrium constant

Which of the following does not need to be included in the equilibrium expression a. pure gases b. pure liquids c. pure solids d. both b and c

d. both b and c

The species that remains after a Bronsted acid has given up a proton is a. weak acid b. weak base c. conjugate acid d. conjugate base

d. conjugate base

2SO3(g) <--> 2SO2(g) + O2(g) delta H not = +198kJ Which would not cause equilibrium to shift to left: a. Add some SO2 b. Remove some SO3 c. Decrease the temperature d. Increase the container volume

d. increase container volume Adding product will cause shift to left Removing reactant will cause shift to left Decreasing T will cause shift to left endothermic Increasing V will decrease P causing shift toward larger # of moles of gas (right)

By the Arrhenius definition, a base a. produces an H+ ion in water b. reacts with a metal to produce H2 gas c. feels slippery on skin d. produces an OH- ion in water

d. produces an OH- ion in water

For an exothermic reaction, increasing the reaction temperature results in a(n) ______ in K.

decrease

Consider the following reaction at equilibrium: 2CO₂ (g) ↔ 2CO (g) +O₂ (g) delta H° = -514 kj Le Chatelier's principle predicts that an increase in temperature will ______.

decrease the value of the equilibrium constant

The solubilities of gases in water generally ------with increasing ----------.

decrease, temperature

Increasing pressure ________ volume, and favors _________.

decreases, products

Consider the following reaction at equilibrium: C (s) + H2O (g) = CO (g) + H2 (g) Which of the following conditions will increase the partial pressure of CO?

decreasing the pressure in the reaction vessel

quantitative analysis

determines how much of a given substance is present.

qualitative analysis

determines only the presence or absence of a particular metal ion

List all the IM Forces present in a sample of SO2

dipole-dipole dispersion

The half-life for a first order rate law ________ on the starting concentration.

doesn't depend

nonelectrolyte

doesn't ionize in water at all

Acid

donates a proton to H2O

Which of the following statements is true? Oxidation and reduction a. cannot occur independently of each other b. accompany all chemical changes c. describe the loss and gain of electrons respectively d. result in a change in the oxidation states of the species involved. e. a, c, and d are true

e. a, c, and d are true

Which has lowest boiling point: a. 1.0m glucose in water 1.0m b. 1.0m NaCl in water 2.0m c. 1.0m NaBr in water 2.0m d. 1.0 CaCl2 in water 3.0m e. water 0.0m

e. water Lowest bp is soln with smallest molality of particles

Heat + NH₄Cl (s) ↔ NH₃ (g) + HCl (g) Is the equilibrium reaction exothermic or endothermic?

endothermic

the point at which stoichiometrically equivalent quantities of acid and base have been brought together

equivalence point

The equilibrium shifts in the direction that consumes the _______ namely heat.

excess reactant

H₂ (g) + I₂(g) ↔ 2HI 9G) + heat Is the equilibrium reaction exothermic or endothermic?

exothermic

Metallic solids do not exhibit __________.

extreme brittleness

Adding a catalyst shifts the direction of reaction in an equilibrium system

false

At constant temperature, reducing the volume of a gaseous equilibrium mixture causes the reaction to shift in the direction that increases the number of moles of gas in the system.

false

If a first order reaction is 87.5 % complete (one eighth left unreacted) in 60 minutes then its half-life is 30 min and the rate constant k = 0.0231 min-1

false

True/False The oxidation number for Chlorine is always -1

false

True/False When hydrogen is combined with a metal, its oxidation number is + 1

false

True/false When an atom is oxidized in a redox reaction, its oxidation number decreases

false

__ The value of an equilibrium constant changes on changing the pressure.

false

In which of the following aqueous solutions would you expect AgBr to have the highest solubility?

for a question like that look for common ions.. those will decrease solubity for this pure water would be best from the choices

K(f) stands for

formation constant

Reactant quotient Q :

found by substituting reactant and product concentrations or partial pressures at any point during a reaction into the equilibrium-consant expression

Which one of the following processes produces a decrease in the entropy of the system?

freezing water to form ice

Which one of the following processes produces a decrease in the entropy of the system? A) boiling water to form steam B) dissolution of solid KCl in water C) mixing of two gases into one container D) freezing water to form ice E) melting ice to form water

freezing water to form ice

on a molecular level, reaction rates depend on the

frequency of collisions between molecules-the greater the frequency of collisions, the higher the reaction rate

The lower right area of a phase diagram indicates the ________ for the substance.

gas phase

In general, as temperature goes up, reaction rate __________.

goes up regardless of whether the reaction is exothermic or endothermic

Catalyst that has a different phase from the reactants =

heterogeneous catalyst (finely divided metals are often used as heterogeneous catalysts for soln-and-gas phase r x n's

A catalyst that is present in the same phase as the reacting molecules is called a ________ catalyst

homogeneous

H₂ (g) + I₂(g) ↔ 2HI 9G) + heat is the equilibrium reaction homogeneous or heterogeneous?

homogeneous

Which of the following could be added to a solution of potassium fluoride to prepare a buffer? sodium hydroxide potassium acetate hydrochloric acid sodium fluoride ammonia

hydrochloric acid

The dissolution of water in octane (C8H18) is prevented by __________.

hydrogen bonding between water molecules

bases react in water in a ...... reaction to form ........

hydrolysis; OH⁻ and the conjugate acid X⁻ + H₂O ↔HX + OH⁻

bases with OH- ions are named as the ________ of the metal in the formula

hydroxide

Differences in a solvent-solute as compared with solvent-solvent and solute-solute intermolecular forces cause many solutions to depart from -------- ---------

ideal behavior

will a precipitate form?

if Q = k(sp) → system is at equilibrium and solution is saturated Q < K(sp) →more solid can dissolve until equilibrium is reached Q>K(sp)→ salt will precipitate until equilibrium is reached

) The effect of a catalyst on an equilibrium is to __________. A) slow the reverse reaction only B) shift the equilibrium to the right C) increase the equilibrium constant so that products are favored D) increase the rate of the forward reaction only E) increase the rate at which equilibrium is achieved without changing the composition of the equilibrium mixture

increase the rate at which equilibrium is achieved without changing the composition of the equilibrium mixture

If you know the value of K =

it is possible to calculate the equilibrium amounts of reactants and products, often by the soln. of an equation in which the unknown is the change in a partial pressure or concentration.

Heat + NH₄Cl (s) ↔ NH₃ (g) + HCl (g) if pressure is increased, will the reaction shift to the right, left, or no change

left

The activation energy of a reaction is 159 kJ/mol. If the rate constant is 2.52 x 10-5/s at 462.7 K, what is the rate constant at 430 K?

ln(2.52 x 10-5/k2) = [1.59 x 105/8.314](1/430 - 1/ 462.7) k2= 1.07 x 10-6 Note that the second temperature is lower than the first temperature and that k2 is less than k1 as expected

The reaction 2H2O2 → 2 H2O + O2 is first order with a rate constant = 0.041 min-1. If we start with 0.500 M H2O2 what will the concentration be after 10 min? Let A = H2O2

ln([A]t/[A]o) = -kt ln([H2O2)t /[0.500]) = -(0.041 min-1)(10 min) [H2O2]t = 0.33 M

Calculate the activation energy for the reaction: 2 N2O5(g) → 4 NO2(g) + O2(g) Given that k1 = 7.78 x 10-7 at T1 = 273 K k2 = 3.46 x 10-5 at T2 = 298 K

ln(k1/k2) = -3.79 = [Ea/8.314](1/298 - 1/ 273) Ea = 1.026 x 105 J/mol

What are the principal organs that regulate the pH of the carbonic acid-bicarbonate buffer system in the blood? a. kidneys, liver b. lungs, kidneys c. spleen, liver d. lungs, skin e. brain stem, heart

lungs, kidneys

You have a solution of NaOCl labeled 3.62 mass % in water. Now calculate the molality of the NaOCl given

m = moles/ kg solvent We have 0.0486 mol NaOCl We have 96.38 g water = 0.09638 kg m = 0.0486 mol / 0.09638 kg = 0.505 m

catalysts

materials that speed up reactions -are agents that increase reaction rates without themselves being used up

when titrating weak base with a strong acid which pH indicator should we use

methyl red (good for ph range 4.2-6.0)

Le Chatelier's principle states that if a system at equilibrium is disturbed, the equilibrium will shift to ________.

minimize the disturbance

Represents the increase in boiling point for a 1 m solution of solute particles as compared with the pure solvent

molal boiling point elevation level, Kb

Measures the lowering of the freezing point of a solution for a 1 m solution of solute particles

molal freezing point depression constant, Kf The temperature changes are given by the equations Delta Tb = Kbm and Delta Tf = Kfm

Moles of solute per kg of solvent ---

molality, m

bases with O2- ions are named as the ________ of the metal in the formula

oxide

Given the following table of thermodynamic data, Substance Delta Hf (kJ/mol) S° (J/mol*K) PCl3 (g) -288.07 311.7 PCl3 (l) -319.6 217 complete the following sentence. The vaporization of PCl3 (l) is ____.

non spontaneous at low temperature and spontaneous at high temperature

A result of the common-ion effect is __________.

that the selective precipitation of a metal ion, such as Ag+, is promoted by the addition of an appropriate counterion (X-) that produces a compound (AgX) with a very low solubility

In a solution, when the concentrations of a weak acid and its conjugate base are equal.

the -log of the [H+] and the -log of the Ka are equal.

the relationship between k and temperature is given by

the Arrhenius Equation: k = Ae ^-Ea/RT the term A = frequency factor and relates to # of collisions favorable for r x n. Arrhenius equation often used in logarithmic form: ln k = ln A - Ea/RT ; a graph of ln k versus 1/T yields a straight line with slope -Ea/R.

Solubility

the ability of one substance to dissolve in another at a given temperature and pressure

at each point below the equivalence point the pH of a solution during titration is determined from....

the amounts of the acid and its conjugate base present at that particular time

chemical kinetics

the area or chemistry concerned with the speeds, or rates of reactions -it relates to how quickly a medicine works in the boyd, towhether the processes that from and deplete ozone in the atmosphere are in balance, and to such industrial challenges as the development of the catalysts

A catalyst increases the rate at which equilibrium is achieved but does not change _______

the composition of the equilibrium mixture

What change will be caused by addition of a small amount of HCl to a solution containing flouride ions and hydrogen fluoride?

the concentration of flouride ion will decrease and the concentration of hydrogen flouride will increase

If the volume of system is reduced

the equilibrium will shift in the direction that decreases the number of gas molecules.

At equilibrium, ________. all chemical reactions have ceased the rates of the forward and reverse reactions are equal the rate constants of the forward and reverse reactions are equal the value of the equilibrium constant is 1 the limiting reagent has been consumed

the rates of the forward and reverse reactions are equal

When Q < K

the reaction will move toward equilibrium by forming more products (r x n proceeds from left to right)

When Q > K

the reaction will proceed from right to left

The shape of a liquid's meniscus is determined by __________.

the relative magnitudes of cohesive forces in the liquid and adhesive forces between the liquid and its container

reaction rate

the speed at which a chemical reaction occurs

percent error formula

|Accepted Value - expirimental Value| \ accepted value x 100%

The magnitude of Kw indicates that ____.

water authorizes only to a very small extent

The magnitude of Kw indicates that __________.

water autoionizes only to a very small extent

Some things take longer to cook at high altitudes than at low altitudes because __________.

water boils at a lower temperature at high altitude than at low altitude

strong acids have ______ conjugate bases

weak

strong bases have _____ conjugate acids

weak

strong acids/bases = strong electrolytes

weak acids/bases= weak electrolytes

Hydrated metal ions act as _____ _____ which interrupts the _______.

weak acids; amphoterism

smaller K(a) means

weaker acid

common ion effect

whenever a weak electrolyte and a strong electrolyte contain a common ion are together in solution, the weak electrolyte ionizes less than it would if it were alone in solution. The ionization of a weak base is also decreased by the addition of a common ion.

At 400 K, the equilibrium constant for the reaction Br2 (g) + Cl2 (g) 2BrCl (g) is Kp = 7.0. A closed vessel at 400 K is charged with 1.00 atm of Br2 (g), 1.00 atm of Cl2 (g), and 2.00 atm of BrCl (g). Use Q to determine which of the statements below is true.

x

Of the following equilibria, only ________ will shift to the right in response to a decrease in volume.

x

The Keq for the equilibrium below is 0.112 at 700.0 °C. What is the value of Keq at this temperature for the following reaction?

x


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Personal Finance Final Questions

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Chapter 2-- Frequency Distributions and Graphs

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