final chem exam

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Of the units below, ________ are appropriate for a third-order reaction rate constant. M-1s-1 mol/L M-2s-1 s-1 M s-1

! M-2s-1

It was determined experimentally that the reaction rate doubled when the concentration of B was doubled in the following reaction:A + B → CThe reaction is ________ order in B. second one-half third first zero

! first

The equilibrium constant for the gas phase reaction2NH3 <......> (g)N2 (g) + 3H2 (g) is Keq = 230 at 300 °C. At equilibrium, ________. reactants predominate only reactants are present Correct! products predominate roughly equal amounts of products and reactants are present only products are present

! products predominate

Consider the following reaction at equilibrium.2CO2 (g) 2CO (g) + O2 (g) ΔH° = -514 kJLe Cha^telier's principle predicts that the equilibrium partial pressure of CO (g) can be maximizedby 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 pressureE) in the presence of solid carbon

) at low temperature and low pressure

The following reaction occurs in aqueous solution:NH4+ (aq) + NO2- (aq) → N2 (g) + 2H2O (l)The data below is obtained at 25 °C. [NH4+] (M)[NO2-] (M)initial rate (M/s)0.1000.2001.8 ×10 -40.2000.2003.6 × 10 -4 The order of the reaction in NH4+ is ________. -1 -2 +1 +2 0

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

Calculate the freezing point of a 0.07500 m aqueous solution of glucose. ΔTf=−i⋅m⋅Kf Glucose's van't Hoff factor, i, is 1 because it is a molecular compound. Water's freezing point is 0 oC. m is the molality of the solution. The molal freezing-point-depression constant of water, Kf, is 1.86 oC/m.

-0.140

Calculate the freezing point of a 0.09500 m aqueous solution of KCl, which dissociates into two ions. i is the van't Hoff factor. m is the molality of the solution. The molal freezing-point-depression constant of water, Kf, is 1.86 ∘C/m. ΔTf=−i⋅m⋅Kf Water has a freezing point of 0 ∘C -0.354 0.0475 -0.0562 -0.177 0.106

-0.354

-1/2 (H2)/daltaT

-1/2(H2) dlta

An aqueous solution contains 0.010 M HNO3. The solution has a [H+]= _________ and pOH = ________. 0.020M; 12.70 0.010M; 2.00 Correct! 0.010M; 12.00 0.020M; 1.30 0.010M; 13.00

0.010M; 12.00

In which of the following aqueous solutions would you expect AgCl to have the lowest solubility? 0.020 AgNO3 0.020 M BaCl2 pure water 0.015 NaCl 0.020 KCl

0.020 M BaCl2

The rate of disappearance of HBr in the gas phase reaction2HBr(g) ⟶ H2(g) + Br2(g) is 0.130 M s-1 at 150°C. The rate of reaction is __________ M s-1. 0.260 0.0650 0.0860 3.85 0.0169

0.0650

Consider a solution containing 0.100 M fluoride ions and 0.126 M hydrogen fluoride. The concentration of fluoride ions after the addition of 4.00 mL of 0.0100 M HCl to 25.0 mL of this solution is __________ M. 0.0876 0.0848 0.0980 0.0862 0.00253

0.0848

The rate of disappearance of HBr in the gas phase reaction2HBr (g) → H2 (g) + Br2 (g)is 0.190 M s-1 at 150 °C. The rate of appearance of Br2 is ________ M s-1. 0.095 0.380 0.0361 0.436 2.63

0.095

The rate of disappearance of HBr in the gas phase reaction2HBr (g) → H2 (g) + Br2 (g)is 0.190 M s-1 at 150 °C. The rate of appearance of Br2 is ________ M s-1. 0.436 2.63 0.095 0.0361 0.380

0.095

Before charging more gas to a bottle that contains 0.450 mol of gas, the bottle has a pressure of 1.00 atm. If the final pressure after charging is 1.50 atm, how many moles of gas were added to the bottle? 0.0450 mol 0.450 mol 2.25 mol

0.225 mol P1/n1 = P2/n2

A sample of a gas (5.0 mol) at 1.0 atm is expanded at constant temperature from 10 L to 15 L. The final pressure is ________ atm. 15 1.5 0.67 7.5 3.3

0.67 PXV=P2XV2

The density of methane gas at 1.21 atm and 34.9 °C is __________ g/L. Molar mass of metahen is 16.0g/mol. D=MPRT D, density M, molar mass Gas law constant, R=0.08206 L⋅atmmol⋅K P, pressure K=273.2 + °C 16.0 6.76 0.765 0.295 0.676

0.765

Of the following solutions, which has the greatest buffering capacity? 0.10 M HC2H3O2 and 0.15 M NaC2H3O2 0.20M HC2H3O2 and 0.95 M NaC2H3O2 0.010 M HC2H3O2 and 0.015 M NaC2H3O2 0.95 M HC2H3O2 and 0.20 M NaC2H3O2 0.85 M HC2H3O2 and 0.75 M NaC2H3O2

0.85 M HC2H3O2 and 0.75 M NaC2H3O2

For each of the following equilibria, write the equilibrium constant expression for Kc. 1. BaSO4(s) .....>Ba2+(aq) + SO42-(aq) 2. HCOOH (aq) + H2O (l)....> HCOO- (aq) + H3O+ (aq)

1- Kc={Ba2+(aq}{SO42-(aq)} 2-Kc={HCOO- }{H3O+ }/{HCOOH }

The Ka of hydrofluoric acid (HF) at 25.0 °C is 6.8 × 10-4. What is the pH of a 0.45 M aqueous solution of HF? 1.76 0.35 4.05 3.64 1.41

1.76

Acetic acid is a weak acid that dissociates into the acetate ion and a proton in an aqueous solution: CH3CO2H (aq) CH3CO2− (aq) + H+(aq)At equilibrium at 25 °C a 0.100 M solution of acetic acid has the following concentrations: [CH3CO2H] = 0.0990M, [CH3CO2−]=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 __________. 5.71 x 104 0.100 1.75 x 10-7 1.79 x 10-5

1.79 x 10-5

alculate the maximum concentration (in M) of silver ions (Ag+) in a solution that contains 0.025M of CO32-. The Ksp of Ag2CO3 is Ksp = [Ag+]2[CO32-] = 8.1 × 10-12. 3.2 x 10-10 1.8 x 10-5 1.4 x 10-6 2.8 x 10-6 8.1 x 10-12

1.8 x 10-5

Given the following reaction at equilibrium, if Kc = 1.90 × 1019 at 25.0 °C, Kp = ________.H2 (g) + Br2 (g) 2 HBr (g) Equation: Kp = Kc(RT)△n 1.56 × 104 5.26 × 10-20 1.90 × 1019 6.44 × 105 none of the above

1.90 × 10^19

Which one of the following graphs shows the correct relationship between concentration and time for a reaction that is second order in [A]?

1/[A] image

A sample of an ideal gas in a closed cylinder at 298 K and 76.0 torr is heated to 613 K. The pressure of the gas in this cylinder at this temperature is __________ torr. 76.5 912 156 39.5 0.0253

156

A sample of gas initially at 4.00 atm was compressed from 8.00 L to 2.00 L at constant temperature. After the compression, the gas pressure was ________ atm. 1.00 2.00 8.00 16.0 4.00

16.0

For the elementary reactionNO3 + CO → NO2 + CO2the molecularity of the reaction is ________, and the rate law is rate = ___________. 4, k[NO3][CO][NO2][CO2] 4, k[NO2][CO2]/[NO3][CO] 2, k[NO3][CO] 2, k[NO2][CO2] 2, k[NO3][CO]/[NO2][CO2]

2, k[NO3][CO]

At STP, the molar volume of an ideal gas is 22.4L. How many moles is 44.8L of an ideal gas? STP: standard temperature and pressure. T=0.00 ∘C and P=1.00atm. 22.4 2.00 14.7 44.8 0.08206

2.00 n=pv/RT

The acid-dissociation constant, Ka, for an unknown acid HA is 4.57 × 10-3. What is the base-dissociation constant, Kb, for the unknown anion A-? 4.57 × 10-3 7.81 × 10-6 2.19 × 102 2.19 × 10-12 5.43 × 10-5

2.19 × 10-12

Given the following reaction at equilibrium, if Kp = 0.990 at 250.0 °C, Kc = __________.PCl5(g) PCl3(g) + Cl2(g) Equation: Kp = Kc(RT)△n 3.90 x 10-6 2.31 x 10-2 0.990 42.9 42.5

2.31 x 10-2

A 25.0-mL sample of 0.150 M butanoic acid is titrated with a 0.150 M NaOH solution. What is the pH before any base is added? The Ka of butanoic acid is 1.5 x 10-5. 1.5 x 10-3 2.83 4.00 4.82 1.0 x 104

2.83

Standard temperature and pressure (STP), in the context of gases, refers to ________. 273.15 K and 1 torr 298.15 K and 1 atm 273.15 K and 1 pascal 298.15 K and 1 torr 273.15 K and 1 atm

273.15 K and 1 atm

The concentration of iodide ions in a saturated solution of lead (II) iodide is __________ M. The solubility product constant of PbI2 is Ksp=[Pb2+][I-]2 = 1.4 X 10-8. 1.5 x 10-3 3.8 x 10-4 1.4 x 10-8 3.0 x 10-3 3.5 x 10-9

3.0 x 10-3

The density of chlorine gas at 1.21 atm and 34.9 °C is __________ g/L. Molar mass of Cl2 is 70.9g/mol. D=MP/RT D, density M, molar mass Gas law constant, R=0.08206 L⋅atmmol⋅K P, pressure K=273.2 + °C 0.0479 1.70 0.295 0.423 3.39

3.39 D=MP/RT 34.9 +273=307.9

What is the pH of an aqueous solution at 25.0 °C that contains 2.50 × 10-4 M hydronium ion? 7.00 2.50 10.4 4.00 3.60

3.60

Calculate the concentration (in M) of hydronium ions in a solution at 25.0 °C with a pOH of 3.58. 2.63 × 1010 3.80 × 10-11 1.00 × 10-7 2.63 × 10-4 3.80 × 103

3.80 × 10-11

A sample of gas (1.5 mol) occupies ________ L at STP. STP: 1.0 atm and 0 ∘C. 33.6 0.079 0.15 1.5 22.4

33.6

Calculate the volume of 3.20 mol of gas at 2.30 atm and 25.0 °C. Show work for full credit. PV=nRT

34.0 L PV=nRT volume ? n=f 3.20 mol p=t 2.30 atm T=25+273=298 R=0.08026

A helium balloon is filled to a volume of 27.7 L at 300 K. What will the volume of the balloon become if the balloon is heated to raise the temperature to 392 K? 0.0472 0.0276 21.2 3,260,000 36.2

36.2

The Keq for the equilibrium below is 0.02. 2HI (g).....> H2 (g) + I2 (g) What is the value of Keq for the following reaction?H2 (g) + I2 .....>(g) 2HI (g)

The pH of a solution prepared by mixing 50.0 mL of 0.125 M KOH and 50.0 mL of 0.125 M HCl is __________. 0.00 5.78 7.00 6.29 8.11

7.00

At 273 K and 4.0 atm, what is the volume of 1.3 mol ideal gas?

7.12L

What is the concentration (in M) of hydronium ions in a solution at 25.0 °C with pH = 4.146? Correct! 7.15 × 10-5 4.15 9.85 none of the above 1.40 × 10-10

7.15 × 10-5

760 torr is equivalent to ________ mm Hg. Please refer to the exam equation and supporting files. 4.78 × 103 121 760 380 1

760

If 3.21 mol of a gas occupies 56.2 L at 44 °C and 793 torr, 4.73 mol of this gas occupies ________ L under these conditions. 82.8 14.7 30.9 478 61.7

82.8

Consider the following reaction at equilibrium:2NH3 (g) N2 (g) + 3H2 (g) ΔH° = +92.4 kJLe Cha^telier's principle predicts that adding N2 (g) to the system at equilibrium will result in__________. A) a decrease in the concentration of H2 ( g)B) a lower partial pressure of N2C) a decrease in the concentration of NH3 (g)D) removal of all of the H2 (g)E) an increase in the value of the equilibrium constant

A) a decrease in the concentration of H2 (

Please read the following statements about gases and select the false one? Gases expand spontaneously to fill the container they are placed in. Distances between molecules of gas are very large compared to bond distances within molecules. All gases are colorless and odorless at room temperature. Gases are highly compressible. Non-reacting gas mixtures are homogeneous.

All gases are colorless and odorless at room temperature.

The Keq for the equilibrium below is 5.4 × 1013 at 480.0 °C.2NO (g) + O2 (g) 2NO2 (g)Which statement of the following one is correct when starting with 2.0M of NO and 1.0 M of O2? At equilibrium, oxygen, O2, has the highest concentration. At equilibrium, [NO2] = 2[NO]. At equilibrium, [NO2] < [NO]. At equilibrium, [NO2] >> [NO]. The reverse reaction has a equilibrium constant Kc= 5.4 × 10-13

At equilibrium, [NO2] >> [NO].

Which of the following is not part of the kinetic-molecular theory? Attractive and repulsive forces between gas molecules are negligible. Collisions between gas molecules do not result in the loss of energy. ! Atoms are neither created nor destroyed by ordinary chemical reactions. Gases consist of molecules in continuous, random motion. The volume occupied by all of the gas molecules in a container is negligible compared to the volume of the container.

Atoms are neither created nor destroyed by ordinary chemical reactions.

"Equal volumes of different gases at the same temperature and pressure contain the same molar amounts" is another way of stating Boyle's law. Avogadro's law. Graham's law. Dalton's law Charles' law.

Avogadro's law.

Consider the following reaction at equilibrium:2CO2 (g) 2CO (g) + O2 (g) ΔH° = -514 kJLe Cha^telier'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

Vapor Pressure

Because of solute-solvent intermolecular attraction, higher concentrations of nonvolatile solutes make it harder for solvent to escape to the vapor phase. Therefore, the vapor pressure of a solution is lower than that of the pure solvent.

Of the following, __________ has the highest boiling point. N2 Cl2 H2 Br2 O2

Br2

The following two-step mechanism consists of two elementary steps, Step 1: Br + O3 → BrO + O2S tepe 2: BrO + O → Br + O2Which species is an intermediate in this mechanism? What is the molecularity of step 2? What is the overall reaction?

BrO is intermediate; As of Br, it is the catalyst. Bimolecular; O3 + O → 2O2

n which of the following reactions would increasing pressure at constant temperature not changethe concentrations of reactants and products, based on Le Cha^telier'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)

Which one of the following substances would be the most soluble in CCl4? C2Cl6 Li2O NH3 HCl CH3CH2OH

C2Cl6

Which of the following substances is more likely to dissolve in CH3OH? N2 Kr CH3CH2OH CCl4 H2

CH3CH2OH

Which molecule below has the highest boiling point? CH3Cl CH3Br CH3F CH4 CH3I

CH3I

Because of the low polarity, of the following molecules, only __________ has London dispersion forces as its only intermolecular force. CH3OH NH3 H2S CH4 HCl

CH4

Of the following substances, only __________ has London dispersion forces as its only intermolecular force. H2S CH4 HCl CH3OH NH3

CH4

Based on the knowledge of the strong acids and bases, ___________will act as a weak base in water? ClO- OH- Cl- None of these will act as a weak base in water. NO3-

ClO-

Based on the knowledge of the strong acids and bases, ___________will act as a weak base in water? ClO- OH- Cl- None of these will act as a weak base in water. NO3-

ClO-

A solution containing which one of the following pairs of substances will be a buffer solution? CsF, HF RbCl, HCl none of these NaI, HI KBr, HBr

CsF, HF

For the endothermic reactionCaCO3 (s) ......>CaO (s) + CO2 (g)Le Cha^telier's principle predicts that __________ will result in an increase in the number of moles ofCO2. 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

Consider the following reaction at equilibrium:2NH3 (g) N2 (g) + 3H2 (g)Le Cha^telier'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)

The effect of a catalyst on an equilibrium is to __________.A) slow the reverse reaction onlyB) shift the equilibrium to the rightC) increase the equilibrium constant so that products are favoredD) increase the rate of the forward reaction onlyE) increase the rate at which equilibrium is achieved without changing the composition of theequilibrium mixture

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

Out of the substances below, __________ is not amphiprotic, capable of acting as both an acid and a base. H2PO4- HSO3- HPO42- F- H2O

F-

Using the Ka data of the four weak acids in the table, which of the conjugate bases below is the weakest? AcidKaHOAc1.8 × 10-5HC7H5O26.3 × 10-5HNO24.5 × 10-4HF6.8 × 10-4 OAc- C7H5O2- NO2- OAc- and C7H5O2- Correct! F-

F-

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. True ! False

False

Rates of reaction can be positive or negative. True False

False

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. True False

False

Which of the following statements of the gaseous mixture is TRUE? Gaseous mixtures can only contain isolated atoms Correct! Gaseous mixtures are all homogeneous Gaseous mixtures must contain both isolated atoms and molecules Gaseous mixtures are all heterogeneous Gaseous mixtures can only contain molecules

Gaseous mixtures are all homogeneous

What is the conjugate acid of HCO3-? Correct! H2CO3 none of the above HCO22- CO32- CO22-

H2CO3

Of the following substances, ________ has the highest boiling point. Ar SiH4 Cl2 BF3 H2O

H2O

What is the conjugate acid of OH-? O- H2O O2- O2 H3O+

H2O

Which molecule has the highest boiling point? CH3CH2CH2CH3 H2O CH4 CH3CH3 CH3CH2CH3

H2O

According to kinetic-molecular theory, in which of the following gases will the root-mean-square speed, μrms, of the molecules be the highest at 200 °C? μ rms = 3RTM , where R is the gas law constant, T is the temperature, and M is the molar mass. HCl, molar mass 36.5g/mol Cl2, molar mass 71g/mol The molecules of all gases have the same root-mean-square speed at any given temperature. H2O vapor, molar mass 18g/mol SF6, molar mass 146.1g/mol

H2O vapor, molar mass 18g/mol b/c smaller mass faster movement

Hydrochloric acid is a strong acid. This means that ________. HCl produces a gaseous product when it is neutralized HCl cannot be neutralized by a weak base HCl does not dissociate at all when it is dissolved in water aqueous solutions of HCl contain equal concentrations of H+(aq) and OH-(aq) ! HCl dissociates completely to H+(aq) and Cl-(aq) when it dissolves in water

HCl dissociates completely to H+(aq) and Cl-(aq) when it dissolves in water

According to kinetic-molecular theory, in which of the following gases will the root-mean-square speed, μrms, of the molecules be the highest at 200 °C? μ rms = 3RTM , where R is the gas law constant, T is the temperature, and M is the molar mass. HCl HF F2 The molecules of all gases have the same root-mean-square speed at any given temperature. Cl2

f the following acids, ________ is not a strong acid. HCl H2SO4 HNO2 HClO4 HNO3

HNO2

Of the following acids, ________ is a strong acid. HClO HNO2 HNO3 H2CO3 HF

HNO3

The conjugate acid of SO42- is ________. H3SO4+ HSO4- HSO42- H2SO4 OH-

HSO4-

Given that all the molecules below are nonpolar, __________ has the lowest boiling point. N2 Br2 He Cl2 O2

What role did Karl Bosch play in development of the Haber-Bosch process? A) Haber was working in his lab with his instructor at the time he worked out the process.B) He originally isolated ammonia from camel dung and found a method for purifying it. C) He developed the equipment necessary for industrial production of ammonia.D) He was the German industrialist who financed the research done by Haber.E) He discovered the reaction conditions necessary for formation of ammonia.

He developed the equipment necessary for industrial production of ammonia

Write the Kc and Kp expressions for the following reaction? And relate Kc to Kp by using the provided equilibrium equation.CO2 (g) + 2H2 (g) ....> CH3OH (g)

Kb=Ka/{RT}^2

The equilibrium expression for Kc for the reaction below is ________.2O3.....> (g) 3O2 (g)

Kc={o2}^3/{o3}^2

By using the gas density equation and given molar masses, choose the gas that has the greatest density at STP. (molar masses: CO2 is 44.0g/mol; Ar is 40.0g/mol; N2 is 28.0g/mol; Kr is 83.8g/mol.) D=MPRT D, density M, molar mass Gas law constant, R=0.08206 L⋅atmmol⋅K P, pressure Ar Correct! Kr N2 CO2 All these gases have the same density.

Of the units below, ________ are appropriate for a second-order reaction rate constant. s-1 M-2s-1 M-1s-1 M s-1 mol/L

M-1 s-1

Of the units below, ________ are appropriate for a third-order reaction rate constant. M-1s-1 mol/L M-2s-1 s-1 M s-1

M-2s-1

Which of the following substances would have the highest boiling point: HBr, H2O, MgCl2, N2? Explain your reasoning.

MgCl2 is higher than water b/c is an ionic compound that needs more energy to break down. the Mg and Cl atoms move electrons within the molecule to create the chemical bonds that make up the molecule. H2O b/c hydrogen bond is stronger for water boiling point 100 C less than Mgcl2 MgCl2 > H2o >HBr> N2

Which one of the following pairs cannot be mixed together to form a buffer solution? NaCl, KCl H2SO3, KHSO3 NH3, NH4Cl KOH, HF KNO2, HNO2

NaCl, KCl

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

NaF

A solution containing which one of the following pairs of substances will be a buffer solution? CH3COOH, HCl none of these ! NaF, HF NH4Br, HBr NaCl, HCl

NaF, HF

solution containing which one of the following pairs of substances will be a buffer solution? CH3COOH, HCl none of these NaF, HF NH4Br, HBr NaCl, HCl

NaF, HF

At 1000 °C, the equilibrium constant of the following reaction: COCl2 (g).....> CO(g) + Cl2(g) has the value of Kc= 0.0219. Calculate Q if we start with 0.200 M COCl2, 0.00330M CO and 0.00662M Cl2. Predict the direction in which the reaction proceeds to reach equilibrium.

Q={CO(g}) { Cl2(g)} /{COCl2 (g).} Kc.>Q so sheft to left

One industrial preparation of methanol uses CO and H2 in the following reaction: CO(g) + 2 H2(g) → CH3OH(g). The reaction rate can be expressed in the rate of disappearance of reactants, and ________ of the following expression is correct? Reaction rate = ? (Reaction rates are confusing for me to remember) After three experiments, the data below were collected for the following reaction at 0 ∘C: 2 NO2 (g) + F2 (g) ⟶2 NO2F (g) Experiment Number[NO2] (M)[F2] (M)Initial Rate (M⋅S-1)10.1000.1000.002820.2000.1000.005630.1000.2000.0112 What is the expression for the rate law of the reaction? (The rate expression is in the format of rate=k[NO2]m[F2]n)

Rate=k[NO2][F2]^2

The dissolution of calcium hydroxide is exothermic:Ca(OH)2(s) ⇌ Ca2+(aq) + 2 OH-(aq)What happens when the solution of Ca(OH)2 is heated? The amount of Ca(OH)2(s) decreases. ! The amount of Ca(OH)2(s) increases. The Ca(OH)2(s) completely dissolves. The amount of Ca(OH)2(s) remains unchanged.

The amount of Ca(OH)2(s) increases.

By applying le chatelier's principle, when the common ion acetate, CH3COO-, was added to the solution of acetic acid, the extent of ionization of acetic acid is decreased. Therefore, __________________. CH3COOH(aq) + H2O(l) CH3COO-(aq) + H3O+(aq) The equilibrium will move to the right. The solution will become more acidic. The solution pH will decrease. The concentration of CH3COOH will decrease. The concentration of H3O+ will increase.

The concentration of CH3COOH will decrease.

The pink and blue species below form a violet colored mixture at equilibrium:[Co(H2O)6]2+ (aq) + 4 Cl- (aq) ⇌ [CoCl4]2- (aq) + 6 H2O (l) (pink)(blue) If the concentration of [Co(H2O)6]2+ is increased, what happens to the solution? The concentration of [CoCl4]2- decreases. The concentration of [CoCl4]2- increases. No color change is observed. The solution becomes colorless.

The concentration of [CoCl4]2- increases.

Which one of the following statements does not describe the equilibrium state? The concentration of the reactants is equal to the concentration of the products. Equilibrium is dynamic and there is no net conversion to reactants and products. The concentration of the reactants and products reach a constant level. The rate of the forward reaction is equal to the rate of the reverse reaction.

The concentration of the reactants is equal to the concentration of the products.

How is the reaction quotient used to determine whether a system is at equilibrium? The reaction quotient must be satisfied for equilibrium to be achieved. At equilibrium, the reaction quotient is undefined. The reaction is at equilibrium when Q < Keq. The reaction is at equilibrium when Q > Keq. The reaction is at equilibrium when Q = Keq.

The reaction is at equilibrium when Q = Keq.

Le Châtelier's principle states that if a system at equilibrium is disturbed, the equilibrium will shift to minimize the disturbance. True False

True

The boiling points of normal hydrocarbons are higher than those of branched hydrocarbons of similar molecular weight because the London-dispersion forces between normal hydrocarbons are greater than those between branched hydrocarbons. True False

True

The overall reaction order is the sum of the orders of each reactant in the rate law. True False

True

The overall reaction order is the sum of the orders of each reactant in the rate law. True False

True

The rate limiting step in a reaction is the slowest step in the reaction sequence. True False

True

The value of the boiling-point-elevation constant (Kb) depends on the identity of the solvent. True False

True

he rate limiting step in a reaction is the slowest step in the reaction sequence. True False

True

Which one of the following is a valid statement of Avogadro's law? V = constant × P V = constant × n PV = constant PT= constant VT = constant

V = constant × n

Consider the following reaction at equilibrium:2NH3(g) N2(g) + 3H2(g) ΔH = + 924kJ Le Châtelier's principle predicts that adding N2 (g) to the system at equilibrium will result in __________. a decrease in the concentration of NH3 (g) a decrease in the concentration of H2 (g) an increase in the value of the equilibrium constant a lower partial pressure of N2 removal of all of the H2 (g)

a decrease in the concentration of H2 (g)

One significant difference between gases and liquids is that ________. All of the above answers are correct. a gas is made up of molecules gases are always mixtures a gas may consist of both elements and compounds a gas expands to fill its container

a gas expands to fill its container

A 25.0 mL sample of a solution of an unknown compound is titrated with a 0.115 M NaOH solution. The titration curve above was obtained. The unknown compound is __________. a weak acid a strong base a strong acid a weak base

a weak acid

n aqueous solution of a particular compound has pH = 6.76. The compound is ________. a strong acid a salt a weak acid a weak base a strong base

a weak acid

A Br∅nsted-Lowry base is defined as a substance that ________. acts as a proton donor increases [OH-] when placed in H2O increases [H+] when placed in H2O decreases [H+] when placed in H2O acts as a proton acceptor

acts as a proton acceptor

Which of the following changes in condition will cause the equilibrium below to shift to the right? FeO(s) + CO(g) Fe(s) + CO2(g) add CO2 Add Fe raise the temperature add CO remove FeO

add CO

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. (i) only none (ii) and (iii) all (i) and (iii)

all

The rate of a reaction depends on __________. collision frequency all of these collision orientation collision energy none of these

all of these

Which one of the following is a valid expression for the rate of the reaction below? 4NH3 + 7O2 → 4NO2 + 6H2O 1/6Δ[H2O]Δt -1/7Δ[O2]Δt all of these answers -1/4Δ[NH3]Δt 1 4

all of these answers

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? bromocresol purple phenolpthalein methyl red thymol blue Correct! bromthymol blue

bromthymol blue

The primary buffer system that controls the pH of the blood is the __________ buffer system. carbonate, carbonic acid carbon dioxide, carbonate carbonic acid, carbon dioxide carbonic acid, bicarbonate carbonate, bicarbonate

carbonic acid, bicarbonate

As a gaseous element condenses, the atoms become ________ and they have ________ attraction for one another. more separated, more closer together, less closer together, more more separated, less larger, greater

closer together, more

Consider the following reaction at equilibrium:2CO2(g) 2CO(g) + O2(g) ΔH = -514kJ Le Châtelier's principle predicts that an increase in temperature will __________. increase the partial pressure of O2 (g) decrease the partial pressure of CO2 (g) decrease the value of the equilibrium constant increase the value of the equilibrium constant increase the partial pressure of CO

decrease the value of the equilibrium constant

The reaction below has an enthalpy change, ΔH = +136 kJ. If the reaction takes place in a closed container, which one of the following changes will decrease the concentration of water vapor? 2 NaHCO3(s) ⇌ Na2CO3(s) + CO2(g) + H2O(g) heat the reaction container r decrease the volume of the container remove CO2 add some NaHCO3 remove NaHCO3

decrease the volume of the container

Select the word from the word bank to make each of the following statements true. a. With all other properties being held constant, as pressure increases, volume

decreases

As the concentration of a solute in a solution increases, the freezing point of the solution ________ and the vapor pressure of the solution ________. increases, increases decreases, increases decreases, is unaffected decreases, decreases increases, decreases

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 ________. increases, increases increases, decreases decreases, increases decreases, decreases decreases, is unaffected

decreases, decreases

What types of intermolecular forces exist between CH3OH and H2O? dipole-dipole and ion-dipole ! dispersion forces, dipole-dipole, and hydrogen bonding dispersion forces, dipole-dipole, and ion-dipole dispersion forces, hydrogen bonding, dipole-dipole, and ion-dipole dispersion forces and ion-dipole

dispersion forces, dipole-dipole, and hydrogen bonding

first

Of the following, __________ is an exothermic process. melting subliming freezing boiling all of these are exothermic.

freezing

The weakest interparticle attractions exist between particles of a ________, and the strongest interparticle attractions exist between particles of a ________. solid, liquid solid, gas liquid, gas liquid, solid gas, solid

gas, solid

An ideal gas differs from a real gas in that the molecules of an ideal gas ________. have an average molecular mass have appreciable molecular volumes have a molecular weight of zero have no attraction for one another have no kinetic energy

have no attraction for one another

When solutions of strong electrolytes in water are formed, the ions are surrounded by water molecules. These interactions are described as a case of ________. supersaturation hydration crystallization dehydration saturation

hydration

The predominant intermolecular force in water is ________. hydrogen bonding London dispersion forces ion-dipole forces dipole-dipole forces ionic bonding

hydrogen bonding

What intermolecular force is responsible for the fact that ice is less dense than liquid water? London dispersion forces dipole-dipole forces ion-dipole forces hydrogen bonding ionic bonding

hydrogen bonding

The predominant intermolecular force in water is ________ because of the high electronegativity of ________ atom. ion-dipole forces; hydrogen hydrogen bonding; hydrogen hydrogen bonding; oxygen dispersion forces; oxygen dipole-dipole forces; oxygen

hydrogen bonding; oxygen

Which one of the following graphs shows the correct relationship between concentration and time for a reaction that is second order in [A]?

image has 1/[A]

The effect of a catalyst on an equilibrium is to __________. increase the rate of the forward reaction only increase the equilibrium constant so that products are favored slow the reverse reaction only increase the rate at which equilibrium is achieved without changing the composition of the equilibrium mixture shift the equilibrium to the right

increase the rate at which equilibrium is achieved

Consider the following reaction at equilibrium: 2CO2 (g) 2CO (g) + O2 (g)ΔH° = -514 kJ Le Châtelier's principle predicts that a decrease in temperature will ________. increase the value of the equilibrium constant decrease the value of the equilibrium constant increase the partial pressure of CO2 (g) decrease the partial pressure of CO decrease the partial pressure of O2 (g)

increase the value of the equilibrium constant

b. With all other properties being held constant, as temperature increases, volume

increases

c. With all other properties being held constant, as the number of moles increases, volume increases .

increases

The rate law of the overall reactionA+B⟶ Cis rate = k[A]2. Which of the following will not increase the rate of the reaction? All of these will increase the rate. adding a catalyst for the reaction increasing the temperature of the reaction increasing the concentration of reactant A increasing the concentration of reactant B

increasing the concentration of reactant B

For the endothermic gas releasing reactionCaCO3(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 decreasing the temperature increasing the pressure removing some of the CaCO3 (s) none of these

increasing the temperature

When KBr dissolves in water, aqueous K+ and Br- ions result. The force of attraction that exists between K+ and H2O is called a(n) ________ interaction. dipole-dipole hydrogen bonding London dispersion force Correct! ion-dipole ion-ion

ion-dipole

What is the predominant intramolecular force in NaNO3? hydrogen bonding ionic bonding ion-dipole attraction London-dispersion forces dipole-dipole attraction

ionic bonding

If the number of moles of gas is doubled at constant temperature and volume, the pressure of the gas is quadrupled. is doubled. remains the same. is halved. is one-fifth.

is doubled.

If the rate law for the reactionA + 3B → C + 2Dis first order in A and first order in B, then the rate law is rate = _______. k[B] k[A]/[B]3 k[A][B] k[A] k[A][B]3

k[A][B]

If the rate law for the reactionA + 3B → C + 2Dis first order in A and first order in B, then the rate law is rate = _______. k[B] k[A]/[B]3 k[A][B] k[A] k[A][B]3

k[A][B]

The volume of 350. mL of gas at 25°C is decreased to 125 mL at constant pressure. What would the final temperature of the gas be? higher than 25 °C higher than 273 + 25 K same as 25°C lower than 25 °C equal 273 + 25 K

lower than 25 °C

What are the principal organs that regulate the pH of the carbonic acid-bicarbonate buffer system in the blood? kidneys, liver lungs, skin lungs, kidneys brain stem, heart spleen, liver

lungs, kidneys

Pairs of liquids that will mix in all proportions are called ________ liquids miscible unsaturated polar liquids saturated supersaturated

miscible

Which of the following is not a unit of pressure? mm Hg mm Pa psi atm

When KBr dissolves in water, aqueous K+ and Br- ions result. The force of attraction that exists between K+ and the _________ end of H2O molecule is called a(n) ________ interaction. positive; ion-dipole positive; dipole-dipole negative; ion-dipole negative; hydrogen bonding negative; dipole-dipole

negative; ion-dipole

A mixture of He and Ne at a total pressure of 1.6 atm is found to contain 0.32 mol of He and 0.56 mol of Ne, what is the partial pressure of Ne in atm?

p1/P total = n1/n total n total= 0.32 mol of He+ 0.56 mol of Ne=0.88 mol total pressure=1.6 atm pNe/1.6 atm = 0.56 mol of Ne/0.88 mo =1.02 atm

Which solution below has the lowest concentration of hydroxide ions? pH = 8.3 pH = 3.0 pH = 11 pH = 6.0 pH = 12.5

pH = 3.0

According to the Henderson-Hasselbalch equation, in a buffer solution, when the concentrations of a weak acid and its conjugate base are equal, _____________________. the system is not at equilibrium. the[H+] and [OH-] are equal. the buffering capacity is significantly decreased. the pH and pKa are equal. all of these are true.

pH and pKa are equal.

Which of the pressure unit is the SI unit? torr pascal newton atmospheric pressure (atm) mmHg

pascal

The phrase "like dissolves like" refers to the fact that ________. gases can only dissolve other gases polar solvents dissolve polar solutes and nonpolar solvents dissolve nonpolar sol solvents can only dissolve solutes of similar molar mass condensed phases can only dissolve other condensed phases polar solvents dissolve nonpolar solutes and vice versa

polar solvents dissolve polar solutes and nonpolar solvents dissolve nonpolar sol

The ease with which the charge distribution in a molecule can be distorted by an external electrical field is called the ________. electronegativity viscosity polarizability volatility hydrogen bonding

polarizability

The ease with which the charge distribution in a molecule can be distorted by an external electrical field is called the ________. hydrogen bonding electronegativity viscosity polarizability volatility

polarizability

The equilibrium constant for the gas phase reaction2SO2 (g) + O2 (g) 2SO3 (g)is Keq = 2.80 × 102 at 999 K. At equilibrium, ________. products predominate reactants predominate roughly equal amounts of products and reactants are present only products are present only reactants are present

products predominate

Colligative Properties

properties that depend on the concentration of solute particles but not on their identity. Colligative properties depend only on the quantity, not on the identity of the solute particles.• Among colligative properties are- Vapor-pressure lowering - Boiling-point elevation- Freezing-point depression- Osmotic pressure

After three experiments, the data below were collected for the following reaction at 0 ∘C: 2 NO2 (g) + F2 (g) ⟶2 NO2F (g) What is the expression for the rate law of the reaction? (The rate expression is in the format of rate=k[NO2]m[F2]n)

rate=k[NO2]1[F2]2

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

reactant molecules collide more frequently and with greater energy per collision

The equilibrium constant for the gas phase reaction2SO3 (g)2SO2 (g) + O2 (g) is Keq = 0.0036 at 999 K. At equilibrium, ________. only products are present Correct Answer reactants predominate only reactants are present You Answered products predominate roughly equal amounts of products and reactants are present

reactants predominate

A reaction was found to be zero order in A. Increasing the concentration of A by a factor of 2 will cause the reaction rate to ________. increase by a factor of 4 triple remain constant decrease by a factor of the square root of 2 increase by a factor of 8

remain constant

Pure __________ and pure __________ are excluded from equilibrium-constant expressions.

solids--liquids

A 1.0 M Ba(OH)2 solution is ________ that has [OH-] _________. strongly basic; =0.5M weakly basic; = 1.0M weakly acidic, =1.0M strongly basic; =1.0M strongly basic; =2.0M

strongly basic; =2.0M

the pH and pKa are equal.

At equilibrium, ________. the rates of the forward and reverse reactions are equal all chemical reactions have ceased the value of the equilibrium constant is 1 the limiting reagent has been consumed the rate constants of the forward and reverse reactions are equal

the rates of the forward and reverse reactions are equal

Viscosity is __________. the "skin" on a liquid surface caused by intermolecular attraction the resistance to flow the same as density inversely proportional to molar mass unaffected by temperature

the resistance to flow

A balloon contains 0.76 mol N2, 0.18 mol O2, 0.031 mol He and 0.026 mol H2 at 739 mm Hg. What is the partial pressure of O2 in mmHg? Please show work.

total n=0.76 mol N2+ 0.18 mol O2+ 0.031+0.026 mol H2 =0.997 mol x=n for o2/total mle of gases x=0.18 mol/0.997 mol=0.181 Po2= x . total P Po2=0.181 .739 mm Hg=133.8 mmHg

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 water boils at a higher temperature at high altitude than at low altitude heat isn't conducted as well in low density air natural gas flames don't burn as hot at high altitudes

water boils at a lower temperature at high altitude than at low altitude

Which energy difference in the energy profile below corresponds to the reaction heat for the forward reaction? x + y x y - x x - y y

Which energy difference in the energy profile below corresponds to the reaction heat for the forward reaction? x + y You Answered x y - x x - y y

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