Chemistry II, CHM102 MasteringChemistry Ch. 15, 14.2 Acid-base Properties of Water, ALL KNEWTON TESTS, chemistry quiz 1, Gen Chem 2 Acid-Base Review, Fundamentals of Equilibrium, Le Chatelier's Acids Bases Intro, Knewton's Alta Module 14, CH 13 HW 5...

A small amount of product is removed from a system at equilibrium. Which of the following will change? Select all that apply.

- The amount of reactants - The value of Q

For the following equilibrium: 2A+B↽−−⇀C+2D If equilibrium concentrations are [A]=1.5 M, [C]=1.1 M, and [D]=0.68 M, and Kc=0.27, what is the equilibrium concentration of B?

.84 M

For the following equilibrium: 2A⇌B+C If equilibrium concentrations are [A]=0.95 M, [B]=0.45 M, and [C]=1.8 M, what is the equilibrium constant?

.90

When pure reactants are mixed together, at the instant before the forward reaction begins, what will be the numerical value of the reaction quotient, Q?

0

What will be the product formed by the oxidation of 4-hydroxy phenol?

0 II II 0

PH of an acidic solution

0-6 (lower than 7)

Calculate the value of the equilibrium constant, Kc , for the system shown, if 0.1908 moles of CO2, 0.0908 moles of H2, 0.0092 moles of CO, and 0.0092 moles of H2O vapor were present in a 2.00 L reaction vessel at equilibrium. CO2 g+H2 g⇌CO g+H2O g

0.0049

Which value for Kc indicates an equilibrium that strongly favors reactants?

0.00496

The half-life of a radioisotope is 50.0 seconds. What is the rate constant k for the radioactive decay of this isotope?

0.0139 s

Consider the reaction below. The initial concentration of HCN is 0.0183 M, and the initial concentrations of H+ and CN− are each 0.0 M. If the equilibrium constant is Kc=4.9×10−4 under certain conditions, what is the equilibrium concentration of HCN? HCN(aq)↽−−⇀H+(aq)+CN−(aq)

0.016

What is the hydroxide concentration in a solution at 25.0∘C with [H3O+]=5.9×10−13 M? Report your answer with two significant figures.

0.017M

The initial concentrations of PCl3 and Cl2 in the reaction below are each 0.0371 M. If the initial concentration of PCl5 is 0 M and the equilibrium constant is Kc=0.021, what will be the concentration of PCl3 when the system reaches equilibrium? PCl5(g)↽−−⇀PCl3(g)+Cl2(g)

0.019 M

Find the equilibrium expression for the reversible reaction below. 2NO(g)+Cl2(g)⇌2NOCl(g)

Kc=[NOCl]^2 ----- [NO]^2[Cl2]

Titration

Lab procedure to determine amount of acid or bade

Which of the following helps us to predict the effect of change in temperature on a reaction system?

Le Châtelier's principle

Le Châtelier's principle is best described by which of the following descriptions?

Le Châtelier's principle states that when a chemical system at equilibrium is disturbed, the system will return to equilibrium by counteracting the disturbance.

What types of intermolecular forces can be found in ketones?

London dispersion forces dipole-dipole interactions

Ammonia is formed by the reaction of nitrogen gas and hydrogen gas. These species exist in an equilibrium that is described by the following equation. N2(g)+3H2(g)↽−−⇀2NH3(g) ΔH=−92.2kJ/mol

Low temperature favors the formation of ammonia but reduces the rate of reaction, and so the catalyst is used to increase the rate of reaction. The formation of ammonia from hydrogen and nitrogen is an exothermic process: N2(g)+3H2(g)↽−−⇀2NH3(g) ΔH=−92.2kJ/mol Thus, increasing the temperature to increase the rate lowers the yield. If we lower the temperature to shift the equilibrium to favor the formation of more ammonia, equilibrium is reached more slowly because of the large decrease of reaction rate with decreasing temperature. Part of the rate of formation lost by operating at lower temperatures can be recovered by using a catalyst. The net effect of the catalyst on the reaction is to cause equilibrium to be reached more rapidly. It is important to note that the catalyst is not consumed in the process.

Methylamine (CH3NH2) is a weak base like ammonia (NH3). Write the chemical equation for the dissociation of aqueous methyl amine. Be sure to show all charges and include all products.

Methylamine has no OH− anion to dissociate directly. Instead, like ammonia, it has a nitrogen with a lone-pair of electrons that can accept a proton from water, leading to the protonated formula CH3NH+3(aq). The water molecule minus a proton gives the hydroxide anion, OH−(aq). The completed reaction is shown below. CH3NH2(aq)+H2O(l)⇌CH3NH+3(aq)+OH−(aq)

Titration is calculated in....

Molarity

What is the conjugate base of NH3?

NH2^-

There is a base on the left side of the reaction below. Identify the compound in the equation that is a conjugate acid to that base. H2O+NH−2↽−−⇀OH−+NH3

NH3

What is the conjugate acid when the following reaction proceeds in the forward direction? H2O + NH−2 ↽⇀ OH− + NH3

NH3

Which pair, when equal concentrations are mixed, can act as a buffer?

NH3 and NH4Cl HF and KF

Which of the following is directly controlled in a nuclear power plant?

NOT CORRECT!!!!! The number of neutrons produced by each nucleus undergoing fission in the nuclear fuel NOT CORRECT!!!!!

Supercritical mass is:

NOT CORRECT!!!!!! the amount of fissionable material that cannot sustain a chain reaction. NOT CORRECT!!!!!!

Convert an absorbed dose of 5.05rad of neutron radiation into Sv units. Use an RBE of 2.00 for neutron radiation.

NOT CORRECT!!!!!!!! 101.1Sv NOT CORRECT!!!!!!!!

What is the chemical equilibrium that would generate the following equilibrium constant expression: Kc=[SO3]^2 ------------- [O2][SO2]^2

O2+2SO2→2SO3

NH3(aq)+HCl(aq)⇌NH4Cl(aq) The combination of the strong acid HCl and a weak base NH3 forms a weakly acidic solution.

Of the following, which forms a weakly acidic solution? Assume all acids and bases are combined in stoichiometrically equivalent amounts. NH3(aq)+HCl(aq)⇌NH4Cl(aq) HClO4(aq)+LiOH(aq)⇌LiClO4(aq)+H2O(l) 2HI(aq)+Ca(OH)2(aq)⇌CaI2(aq)+2H2O(l) 2HNO3(aq)+Sr(OH)2(aq)⇌Sr(NO3)2(aq)+2H2O(l)

Which of the following do not result from the addition of more reactants to a chemical system at equilibrium? (select all that apply)

Only one of the reactants will be consumed. The value of K increases.

Which of the following is NOT true regarding a system in equilibrium?

Only the concentration of the reactants is constant.

Why is a carbonyl group polar?

Oxygen is significantly more electronegative than carbon.

What will be the Kp for the following equilibrium: Cl2(l)→Cl2(g)

PCl2(g)

Which of the following statements comparing beta decay and positron emission are NOT true?

Particles released during both types of decay processes are deflected the same way in an electric field

Which of the following gives the definition of percent ionization of a weak acid?

Percent ionization is the ratio of the concentration of the ionized acid at equilibrium to the initial acid concentration times 100%.

Transition interval

Ph range over which an indicator changes color

Which of the following is a result of increasing the temperature of a system that includes a reaction in the forward direction that is exothermic?

The equilibrium constant decreases.

2-heptanone is less dense than water and only slightly soluble in water, so as a result, 2-heptanone floats on water. Which among the following statements is true as it relates to its insolubility?

Since 2-heptanone has more than 5 carbons, it is insoluble in water. The effect of the nonpolar alkyl groups dominates over the effects of the carbonyl group.

Which is an example of the chemical nature of substances affecting the rate of reaction? -Sodium oxidizes overnight whereas iron takes much longer -Large pieces of iron react slowly with acids while finely divided iron reacts more rapidly -Food spoils more quickly on the kitchen counter than in the fridge all of the above

Sodium oxidizes overnight whereas iron takes much longer

Which of the following solutions has a greater concentration of hydroxide ions? Solution A has a pOH of 6.1. Solution B has a pOH of 12.5.

Solution A

Characteristics properties do buffered solutions possess?

Solution that resists ph change

What's the difference between a Strong acid-weak base Weak acid-strong base

Strong acids and bases are completely ionized in solution Weak acids and bases are partially dissociated in solution

Of the following, which is a result of decreasing the temperature of an exothermic system?

The equilibrium constant increases.

What type of electrolyte will a strong acid or base be?

Strong electrolyte

What's in indicator?

Substances that exhibit different colors in an acidic or basic solutions. Ex: ph paper

The melting point of phenol is 40.5∘C and that of toluene is −95∘C. What is the best explanation for this difference?

The (−OH) group on phenol can form hydrogen bonds, and the −CH3 group on toluene cannot.

equation of Ka

The Henderson-Hasselbalch equation is derived from the:

determining concentrations of buffer components for a target pH. We can use tabulated pKa values to select suitable buffer components close to the desired pH, and then make finer pH adjustments by varying the concentrations. The Henderson-Hasselbalch equation gives a relatively simple formula (compared to making an I.C.E. box and solving the resulting algebra) to find the pH of a buffer solution from the pKa and the concentration

The Henderson-Hasselbalch equation is useful for:

Identify the option below that is true of buffers.

The ability of a buffer to resist changes in pH is directly dependent on the concentrations of the buffering species it contains.

What will determine the number of moles of hydronium in an aqueous solution of a strong monoprotic acid?

The amount of acid that was added.

Consider the following chemical equation to answer the question that follows. A+B↽−−⇀C+D An additional amount of reactant A is added to a system at equilibrium. Which of the following will change as equilibrium is reestablished?

The amount of reactant A. The amount of reactant B. The amounts of the products.

A small amount of product is removed from a system at equilibrium. Which of the following will change? Select all that apply.

The amount of reactants The value of Q

A small amount of product is removed from a system at equilibrium. Which of the following will change? Select all that apply. -The amount of reactants -The value of the equilibrum constant -The value of Q -The temperature associated with the equilibrium constant describing this system

The amount of reactants The value of Q

slightly basic The bloodstream has a pH of around 7.35, which is just slightly basic.

The bloodstream is:

1 pH unit

The buffer capacity of a solution has been exceeded when the pH of the solution has changed by at least

diminish slowly until buffer capacity is reached, then begin to diminish rapidly

The buffering ability of a solution will

Consider the equilibrium between NO2 and N2O4. How can you tell if you are at equilibrium?

The color in the tube stops changing.

An endothermic reaction proceeds in the forward direction. Which of the following statements will be true if the temperature at which the reaction occurs is decreased?

The concentrations of the products decrease. The equilibrium constant decreases.

Which of the following are results of increasing the temperature of a system that includes an endothermic reaction in the forward direction? (select all that apply)

The concentrations of the products increase. The concentrations of the reactants decrease.

Which of the following are results of increasing the temperature of a system that includes an endothermic reaction in the forward direction?

The concentrations of the products increase. The concentrations of the reactants decrease. In an endothermic reaction, heat can be considered as a reactant. Thus, increasing the temperature is like adding more of a reactant, which will result in a shift toward the products. The concentrations of reactants decrease and the concentrations of the products increase.

Identify the options below that are results of decreasing the temperature of a system that includes an exothermic reaction in the forward direction. The concentrations of the reactants increase. The concentrations of the products increase. The equilibrium shifts toward the products. The equilibrium constant decreases.

The concentrations of the products increase. The equilibrium shifts toward the products.

Of the following, which is not a result of increasing the temperature of a system that includes an endothermic reaction in the forward direction?

The concentrations of the reactants increase.

Of the following, which is /not/ a result of increasing the temperature of a system that includes an endothermic reaction in the forward direction?

The concentrations of the reactants increase. In an endothermic reaction, heat can be considered as a reactant. Thus, increasing the temperature is like adding more of a reactant, which will result in a shift toward the products. Because heat is not accounted for in the equilibrium constant, the equilibrium constant increases based on this shift. The concentrations of reactants decrease and the concentrations of the products increase.

For the reaction 2HBr(g) ⇌ H2(g) + Br2(g) K = 2.00 × 10^−19 at 298 K what can be said about this reaction at this temperature?

The equilibrium lies far to the left.

A system involves a chemical reaction that is exothermic in the forward direction. How will the equilibrium shift if the temperature of the system is decreased?

The equilibrium will shift towards the products.

For the reaction H2(g) + I2(g) ⇌ 2HI(g) K= 57.0 at 700 K what can be said about this reaction at this temperature?

The reaction contains significant amounts of products and reactants at equilibrium.

The reactants zinc and hydrochloric acid are involved in a redox reaction. Which of the following is a product of the reaction?

The reaction is Zn(s)+2HCl(aq)⟶ZnCl2(aq)+H2(g).

What will happen to the following equilibrium if the volume of the vessel in which the equilibrium is contained increases? 2CH4(g)⇌C2H6(g)+H2(g)

There will be no change.

What is titration used for

To analyze the acid or base content of a solution

What is a conjugate acid-base pair?

Two substance related by the donating and accepting of a sinkage proton

Titration what is being measured?

Volume

Which of the following is true of water in a base ionization reaction?

Water loses a proton and is acting as an acid.

What two components make up a buffered solution?

Weak acid, conjugate base

What type of electrolyte will a weak acid or base be?

Weak electrolyte

It can absorb a large amount of heat without a large change in temperature.

What does it mean when a substance has a large specific heat capacity?

(CH3)3NH+

What is the chemical formula for the conjugate acid of the base trimethylamine (CH3)3N?

ion-product constant

What is the term used to describe the equilibrium constant for the autoionization of water?

pH=pKa+log[A−][HA] We know the ratio of [HA] to [A−] is 1:4, and the pKa value, so we plug these into the Henderson-Hasselbalch equation: pH=2.3+log(41)=2.9

What will be the pH of a buffer solution containing an acid of pKa2.3, with an acid concentration that is exactly one fourth of that of its conjugate base?

The autoionization of water can be expressed as: A) OH−(aq)+H3O+(aq)⟶2H2O(l) B) OH−(aq)+H+(aq)⟶H2O(l) C) 2H2O(l)⟶H3O+(aq)+OH−(aq) D) 2H2O(l)⟶H3O+(aq)+2OH−(aq)

C) 2H2O(l)⟶H3O+(aq)+OH−(aq)

Hydrogen is used as a rocket fuel because it is very light and reacts explosively and completely with oxygen. For the combustion reaction 2H2(g) + O2(g) ⇌ 2H2O(g) what is the likely magnitude of the equilibrium constant K?

K > 10^3

List the equilibria from largest to smallest equilibrium constant.

KCl2 > KBr2 > KI2

Potassium hydroxide (KOH) and nitric acid (HNO3) react in an aqueous solution. What are the products of the reaction?

KNO3 and H2O

If we plug equilibrium concentrations into the reaction quotient expression, we should be able to calculate

Kc

If we plug equilibrium concentrations into the reaction quotient expression, we should be able to calculate:

Kc

What will be the value of Kp in terms of Kc for the following equilibrium: 2A(g)+B(g)⇋3C(g)

Kc

What will be the value of Kp in terms of Kc for the following equilibrium:2A(g)+B(g)⇋3C(g)

Kc

The rate at which a reaction is proceeding at a specific point in time is called the:

Instantaneous rate

Consider the reaction below. If the initial concentration of the products C and D are both 0M, and at equilibrium the concentration of D increases by 0.037 M, how does the concentration of C change? 3A(g)+4B(g)⇋2C(g)+D(g)

It increases by 0.074 M

Given the reaction below, how will the concentration of D change if the concentration of B decreases by 0.045 M? 3A(g)+2B(g)⇋2C(g)+5D(g)

It increases by 0.113 M.

How does the magnitude of Kp for the reaction 2HI(g) ⇋ H2(g) + I2(g) change if the equilibrium is written 6HI(g) ⇋ 3H2(g) + 3I2(g)?

It is cubed.

What will happen to the following equilibrium reaction if the volume of the container in which the gasses are contained decreases? 2NO2(g)+O2(g)⇌2NO(g)

It will shift to the right.

At equilibrium, the reaction quotient of a system will be equal to:

K

The equilibrium constant for a system will be symbolized by the letter:

K

What is the proper form of the equilibrium constant expression for the equation? N2(g) + O2(g) ⇌ 2NO(g)

K = [NO]^2 / [N2][O2]

If we plug equilibrium concentrations into the reaction quotient expression, we should be able to calculate:

Kc represents the reaction quotient in terms of concentration for a system at equilibrium.

What will be the value of Kp in terms of Kc for the following equilibrium: A(g)+2B(g)→3C(g)+D(g)

Kc(RT)

Before any reaction occurs, the concentration of A in the reaction below is 0.028 M. What is the equilibrium constant if the concentration of A at equilibrium is 0.0098 M? A(aq)⇌2B(aq)+C(aq)

Kc=2.5×10−3

The concentrations of A and B before the reaction below occurs are each 0.077 M. If the concentration of A at equilibrium is 0.0308 M, what is the equilibrium constant? 2A(g)+B(g)⇌2C(g)

Kc=42

Given the reaction below, what is the equilibrium expression? 2CO2(g)+2H2O(g)⇌C2H4(g)+3O2(g)

Kc=[C2H4][O2]^3 --------------- [CO2]^2[H2O]^2

What will be the equilibrium expression for the following equilibrium: C4H8→2C2H4

Kc=[C2H4]^2 ------------- [C4H8]

Question Write the equilibrium expression for the following reaction: 2Fe2O3(s)+3C(s)⇌4Fe(s)+3CO2(g)

Kc=[CO2]3

What is the equilibrium expression for the reversible reaction shown below? 4NH3(g)+7O2(g)⇌4NO2(g)+6H2O(g)

Kc=[NO2]4[H2O]6/[NH3]4[O2]7

The rate at which a reaction proceeds when the reaction first commences is called the:

initial rate

What is the term used to describe the equilibrium constant for the autoionization of water?

ion-product constant

Which is an example of the state of subdivision of the reactants affecting the rate of reaction? -A reaction proceeds more quickly in the laboratory when placed over a Bunsen burner -A reaction slows down as it proceeds calcium reacts with water moderately, sodium reacts with water explosively large pieces of iron react slowly with acids while finely divided iron reacts more rapidly

large pieces of iron react slowly with acids while finely divided iron reacts more rapidly

Based on the following equation, if the concentration of CH3OH(g) doubles, the equilibrium will shift: CO(g)+2H2(g)↽−−⇀CH3OH(g)

left

Based on the following equation, if the pressure decreases, the equilibrium will shift: N2(g)+3H2(g)↽−−⇀2NH3(g)

left

Based on the following equation, if the pressure decreases, the equilibrium will shift:N2(g)+3H2(g)↽−−⇀2NH3(g)

left

Given a reaction that is endothermic in the forward direction, if the temperature is decreased, which way will the equilibrium shift?

left

Given a reaction that is endothermic in the forward direction, if the temperature is decreased, which way will the equilibrium shift?

left If the forward reaction is endothermic, heat is a reactant, so a decrease in heat will cause the equilibrium to shift left in order to regenerate some of the heat that was lost.

Given a reaction that is exothermic in the forward direction, if the temperature is increased, which way will the equilibrium shift?

left If the forward reaction is exothermic, heat is a product, so an increase in heat will cause the equilibrium to shift left in order to use up some of the excess heat.

For the following systems at equilibrium A : 2NOCl(g) ⇌ 2NO(g) + Cl2(g) B : H2(g) + I2(g) ⇌ 2HI(g) classify these changes by their effect.

leftward shift - system A decrease container size no shift -system B increase container size -system B decrease container size rightward shift -system A increase container size

If the forward reaction of an equilibrium is endothermic, the ΔH will have a _______ sign, and the heat can be thought of as a ________

positive, reactant

If the forward reaction of an equilibrium is endothermic, the ΔH will have a _______ sign, and the heat can be thought of as a _________.

positive, reactant

KOH

potassium hydroxide (strong base)

One way to increase the amount of ammonia produced in an industrial setting is to increase the ________ on the system.

pressure

One way to increase the amount of ammonia produced in an industrial setting is to increase the ________ on the system.

pressure In the industrial production of ammonia, one way to increase the yield of ammonia is to increase the pressure of the system.

Which of the following concentrations appear in the numerator of the equilibrium constant expression?

product

Which of the following concentrations appear in the numerator of the equilibrium constant expression? Select the correct answer below: -solid -reactant -product -gas

product

The first postulate of collision theory states that the rate of a reaction is _______ to the rate of reactant collisions.

proportional

Heat is abbreviated as:

q

Once we have initial concentrations listed in the ICE chart, the next step is to calculate:

relative changes in concentration

A patient has symptoms including increased breathing rate, numbness, muscle spasms, and nausea. The blood pH is checked and found to be 7.5 and CO2 pressure is 37 torr. The patient most likely has what condition?

respiratory alkalosis

When considering the effects of concentration changes, reducing the amount of a product _______.

results in a value of Q that is less than K

Question If Q is greater than K, in which direction will the equilibrium proceed?

reverse

If Q is greater than K, in which direction will the reaction proceed?

reverse, converting products into reactants

For the following equation, if heat is decreased, the equilibrium will shift: H2+I2↽−−⇀2HI+heatΔH=−9.4kJ

right

Given a reaction that is exothermic in the forward direction, if the temperature is decreased, which way will the equilibrium shift?

right

Suppose an extra 0.2 mol of gas B are added to an equilibrium mixture described by the reaction below. In which direction do you predict the equilibrium to shift? A(g)+B(g)⇋C(g)+D(g)

right

Given a reaction that is endothermic in the forward direction, if the temperature is increased, which way will the equilibrium shift?

right If the forward reaction is endothermic, heat is a reactant, so an increase in heat will cause the equilibrium to shift right in order to use up some of the excess heat.

RbOH

rubidium hydroxide (strong base)

For the following equilibrium, what will occur if the vessel contracts: C(s)+H2O(g)⇌CO(g)+H2(g)

shift left

If more products are added to a system at equilibrium, the equilibrium will:

shift left

If reactants are removed from a system at equilibrium, the equilibrium will:

shift left

For the following equilibrium, what will occur if the vessel expands: 2O3(g)→3O2(g)

shift right

For the following equilibrium, what will occur if the vessel expands:2O3(g)→3O2(g)

shift right

If products are removed from a system at equilibrium, the equilibrium will:

shift right

pH=pKa+log([A−]/[HA]) pH=3.7+log3 pH=4.2

What will be the pH of a buffer solution containing an acid of pKa3.7, with an acid concentration exactly one third of that of the conjugate base?

An increase in temperature will cause an equilibrium to: shift right shift left no change depends on the equilibrium

depends on the equilibrium

To calculate changes in concentration for a system not at equilibrium, we must first:

determine the direction the equilibrium will move

The rate of a reaction is:

directly proportional the to rate of collisions

In a model that precedes the Bronsted-Lowry model, a base is defined as something that __________.

dissociates in water to yield hydroxide ions

Given the reaction below, how will the concentration of D change if the concentration of B decreases by 0.045 M? 3A(g)+2B(g)⇋2C(g)+5D(g)

increases by .113M

The value of the equilibrium constant, Kc, for a reaction will be __________.

independent of initial concentrations

acid ionization

The reaction between a Brønsted-Lowry acid and water is called

How does the concentration of (H+) to (OH-) compare in a basic solution

(H+)<(OH-)

How does the concentration of (H+) to (OH-) compare in a neutral solution

(H+)=(OH-)

How does the concentration of (H+) to (OH-) compare in a acidic solution

(H+)>(OH-)

Formulas

(H+)MaVa=(OH-)MbVb

For a particular reaction, the change in enthalpy is 51kJmole and the activation energy is 109kJmole. Which of the following could NOT be the change in enthalpy (ΔH) and the activation energy (Ea), respectively, for the catalyzed reaction?

- 34kJmole,83kJmole - 34kJmole,120kJmole - 51kJmole,120kJmole

Which of the following demonstrate homogeneous equilibria? (select all that apply)

- A reaction occurring in a liquid-phase solution - A reaction involving exclusively gaseous species - A reaction between solutes in liquid solution

Which of the following are true statements regarding reversible reactions?

- A reversible reaction might proceed in only one direction, with negligible contribution from the reverse reaction, depending on conditions. - The forward and reverse reactions may occur simultaneously.

The ideal gas law displays the relationship in which of the following? Select all that apply.

- Amontons's law - Charles's law - Boyle's law - Avogadro's law

Which of the following are reactions demonstrating heterogeneous equilibria? (select all that apply)

- Ca(OH)2(s)⇄Ca2+(aq)+2OH−(aq) - H2O(l)⇄H2O(g)

Identify the options below that are false about chemical equilibria. (select all that apply)

- Concentrations of products and reactants oscillate between a set range of values. - At equilibrium, all species have stopped reacting altogether.

Of the following, which are characteristics of basic solutions? Select all that apply.

- Greater concentration of hydroxide ions than hydronium ions - [H3O+] < [OH−]

Based on the reaction below, if the concentration of D decreases by 0.0430 M, what will be the change in concentration for A ? 4A(g)+2B(g)⇋5C(g)+D(g)

.172 M

HClO4 (aq)

perchloric acid (strong acid)

For the following equilibrium: H2+I2⇌2HIKc=50.0 at 400∘C If some of the H2 is removed from a mixture at equilibrium, which of the following changes to the concentrations of I2 and HI will occur as equilibrium is reestablished? Select all that apply.

- The concentration of I2 will increase. - The concentration of HI will decrease.

An endothermic reaction proceeds in the forward direction. Which of the following statements will be true if the temperature at which the reaction occurs is decreased? (select all that apply)

- The concentrations of the products decrease. - The equilibrium constant decreases.

Which of the following are results of increasing the temperature of a system that includes an endothermic reaction in the forward direction?

- The concentrations of the products increase. - The concentrations of the reactants decrease.

Identify the options below that are results of decreasing the temperature of a system that includes an exothermic reaction in the forward direction.

- The concentrations of the products increase. - The equilibrium shifts toward the products.

Which of the following statements about strong acids are true?

- The conjugate base of a strong acid has negligible acid-base properties. - They produce stable ions that have little tendency to accept a proton.

Of the following, which are not results of adding a catalyst to a chemical system at equilibrium?

- The reaction shifts toward the reactants. - The reaction quotient increases. - The equilibrium constant increases.

A strong acid has _______. (select all that apply)

- a large percent ionization - a large Ka value

Which of the following are examples of heterogeneous equilibria? (select all that apply)

- a reaction involving both gases and liquids - a reaction involving a solid and a liquid

Which of the following can result in a change in equilibrium in a reaction involving gases? Select all that apply.

- decreasing the volume of the system to half of its original value - increasing the volume of the system to twice its original value - doubling the amount of one of the components in the system - doubling the amount of all of the components in the system

Which of the following has the potential to change the equilibrium in a reaction involving gases? Select all that apply.

- decreasing the volume of the system to half of its original value - increasing the volume of the system to twice its original value - doubling the amount of one of the components in the system - doubling the amount of all of the components in the system

In the industrial production of ammonia, which of the following is affected by the catalyst? Select all that apply.

- the rate of production - the practical yield that can be obtained in limited time

A catalyst has no effect on: (select all that apply)

- value of an equilibrium constant - equilibrium concentrations

For the following equilibrium: A+2B⇋C+3D If the change in concentration for B is 0.44 M, what will be the change in concentration for C?

-.22

For the following equilibrium: 2A+B→C+2D If the change in concentration for C is 0.36 M, what will be the change in concentration for A?

-.72

For the following equilibrium: A+2B⇋C+3D If the change in concentration for B is +0.44 M, what will be the change in concentration for C?

-0.22

For the following equilibrium: 2A+B→C+2D If the change in concentration for C is 0.36 M, what will be the change in concentration for A?

-0.72

If a neutral acid donates a proton, the conjugate base will have a charge of _______.

-1

Which of the following demonstrate homogeneous equilibria? (select all that apply) -A reaction involving both gases and liquids -A reaction occurring in a liquid-phase solution -A reaction involving exclusively gaseous species -A reaction between solutes in liquid solution

-A reaction occurring in a liquid-phase solution -A reaction involving exclusively gaseous species -A reaction between solutes in liquid solution

Which description best fits the definition of activated complex? -An activated complex is a catalyst present in a different phase from the reactants -An activated complex is a catalyst present in the same phase as the reactants -An activated complex is a molecule or ion produced in one step of a reaction mechanism and consumed in another -An activated complex is an unstable combination of reactant species representing the highest energy state of a reaction system.

-An activated complex is an unstable combination of reactant species representing the highest energy state of a reaction system.

For the equilibrium C2H2+2Br2⇌C2H2Br4 if the initial concentrations are [C2H2]=0.80 M,[Br2]=1.60 M,[C2H2Br4]=0.55 M, and the reaction proceeds in the forward direction until equilibration, where [C2H2]=0.60 M, what is the final concentration (in units of molarity) of C2H2Br4?

.75 M

Which of the following react relatively slowly (hours to years) rather than nearly instantaneously? (select all that apply) -An egg spoiling in a freezer -Calcium exposed to water -Iron train tracks exposed to the air -small pieces of elemental sodium exposed to air

-An egg spoiling in a freezer -Calcium exposed to water -Iron train tracks exposed to the air

An equilibrium constant is described by which of the following? -An equilibrium constant is equal to the molar concentrations of the products multiplied by those of the reactants, with each concentration being raised to the power equal to the coefficient in the equation. -An equilibrium constant is the constant used to scale an equilibrium reaction such that it expresses the formation of exactly 1 mol of product. -An equilibrium constant is the sum of the concentrations or partial pressures of components of a reaction at equilibrium. -An equilibrium constant is the value of the reaction quotient for a system at equilibrium.

-An equilibrium constant is the value of the reaction quotient for a system at equilibrium.

As text, an aldehyde group is represented as:

-CHO

Identify the options below that are false about chemical equilibria. (select all that apply) -There is no net change in the concentrations of the reactants and products. -Concentrations of products and reactants oscillate between a set range of values. -The relative amounts of the reactants and products may not necessarily be equal. -At equilibrium, all species have stopped reacting altogether.

-Concentrations of products and reactants oscillate between a set range of values. -At equilibrium, all species have stopped reacting altogether.

Which of the following are postulates of collision theory? -The rate of a reaction is proportional to the rate of effective reactant collisions. -The reacting species must collide with the optimal orientation to allow the appropriate bonds to break and/or form as reactants are converted to products. -Each collision of reacting atoms results in product formation. -The collision must occur with adequate energy to permit mutual penetration of the reacting species' valence shells so that the electrons can rearrange and form new bonds.

-The rate of a reaction is proportional to the rate of effective reactant collisions. -The reacting species must collide with the optimal orientation to allow the appropriate bonds to break and/or form as reactants are converted to products. -The collision must occur with adequate energy to permit mutual penetration of the reacting species' valence shells so that the electrons can rearrange and form new bonds. (Collision theory relies on three postulates. First, the rate of a reaction is proportional to the rate of reactant collisions. Second, the reacting species must collide in an orientation allowing contact between the atoms that will bond together in the product. And lastly, the collision must occur with enough energy to enable the penetration of valence shells so that electrons rearrange to form new bonds.)

Choose the options below that are true of chemical equilibria. (select all that apply) Select all that apply: -The reaction proceeds in the forward and reverse directions at the same rate. -Both the forward and the reverse reactions are achievable. The relative amounts of all species must be different. There is no net change in concentrations of reactants and products.

-The reaction proceeds in the forward and reverse directions at the same rate. -Both the forward and the reverse reactions are achievable. -There is no net change in concentrations of reactants and products.

Of the following, which are true of chemical equilibria? (select all that apply) -At equilibrium, all reaction species must have a concentration value of 1 M or a partial pressure of 1 atm. --The reaction proceeds in the forward and reverse directions simultaneously. -The amounts of all products and all reactants must be equal at equilibrium. -The forward and reverse reactions occur at equal rates.

-The reaction proceeds in the forward and reverse directions simultaneously. -The forward and reverse reactions occur at equal rates.

An ICE chart is needed to calculate Kc if: -only equilibrium concentrations are given -only initial concentrations are given -a combination of initial and equilibrium concentrations are given -all of the above

-a combination of initial and equilibrium concentrations are given

Which is an example of the chemical nature of substances affecting the rate of reaction? -a reaction proceeds more quickly in the laboratory when placed over a Bunsen burner -a solution containing two moles of each reactant has a faster instantaneous rate of reaction than a solution of the same volume with only one mole of each reactant -calcium reacts with water moderately, sodium can react explosively with water -large pieces of iron react slowly with acids while finely divided iron reacts more rapidly

-calcium reacts with water moderately, sodium can react explosively with water (The difference in rate of reaction between calcium and sodium in water is due to the difference in chemical identity between sodium and calcium. The remaining choices address differences in rate due to temperature (choice a), concentration (choice b), and surface area (choice d).)

Consider the reversible reaction in aqueous medium shown below. At equilibrium, the concentrations of A, B, and C are 0.0102 M, 0.0127 M, and 0.0064 M, respectively. What is the equilibrium constant for the reaction? 3A⇌2B+2C

.0062

Consider the reaction described by the equation below. 4A(g)+5B(g)⇌5C(g)+2D(g) If the initial concentrations of A and B are both equal to 0.100M and the equilibrium concentration of B is 0.0840 M, what is the equilibrium concentration of D?

.0064 M

The equilibrium constant for the reaction shown below is Kc=0.0091. If the equilibrium concentrations of A and B are 0.031 M and 0.0823 M, respectively, what is the equilibrium concentration of C? 3A(aq)⇌3B(aq)+2C(aq)

.022 M

At equilibrium for the reaction in aqueous medium below, the concentrations of A, B, C, and D are 0.011 M, 0.0067 M, 0.0124 M, and 0.0062 M, respectively. What is the equilibrium constant? A+2B⇌3C+D

.024

Consider the reaction below. If the concentration of C decreases by 0.088 M, what will be the change in concentration for A? 2A(g)+3B(g)⇋5C(g)+4D(g)

.035 M

Consider the reaction below. At equilibrium, the concentration of A is 0.0502 M and the concentration of B is 0.057 M. If the equilibrium constant is Kc=3.8038, what is the equilibrium concentration of C? 2A(aq)+B(aq)⇌3C(aq)

.082

Consider the reaction below. At equilibrium, the concentration of A is 0.0502 M and the concentration of B is 0.057 M. If the equilibrium constant is Kc=3.8038, what is the equilibrium concentration of C? 2A(aq)+B(aq)⇌3C(aq)

.082 M

Consider the reaction below. If the concentration of B decreases by 0.068 M, what will be the change in concentration for C? 3A(g)+4B(g)⇋5C(g)

.085

Given the reaction below, if the concentration of B increases by 0.060 M, what will the be the change in concentration of A? 4A(g)+2B(g)⇋3C(g)+D(g)

.120 M

Based on the reaction below, if the concentration of B increases by 0.0830 M, what will be the change in concentration for A? 4A(g)+2B(g)⇋C(g)+2D(g)

.166

Consider the reaction below. At equilibrium, the concentration of A is 0.0333 M and the concentration of B is 0.0831 M. If the equilibrium constant is Kc=10.9499, what is the equilibrium concentration of C? 2A(aq)+3B(aq)⇌3C(aq)

0.0191 M

Under certain conditions, the equilibrium constant of the reaction below is Kc=0.25. If the reaction begins with a concentration of 0.0215 M for I−3 and concentrations of 0.0 M for each of the products, what is the equilibrium concentration of I−? I−3(aq)↽−−⇀I2(aq)+I−(aq)

0.020

The equilibrium constant for the reaction shown below is Kc=0.529. If the equilibrium concentrations of B and C are 0.0798 M and 0.0553 M, respectively, what is the equilibrium concentration of A? 2A(aq)⇌2B(aq)+C(aq)

0.0258 M

Consider the reaction below. The initial concentration of PCl5 is 0.0599 M, and the initial concentrations of PCl3 and Cl2 are each 0.0 M. If the equilibrium constant is Kc=0.021 under certain conditions, what is the equilibrium concentration of Cl2? PCl5(g)↽−−⇀PCl3(g)+Cl2(g)

0.026

Consider the reaction below. At equilibrium, the concentration of A is 0.0242 M and the concentration of B is 0.0767 M. If the equilibrium constant is Kc=0.0266, what is the equilibrium concentration of C? 3A(g)⇌3B(g)+2C(g)

0.029 M

The initial concentrations of I2 and I− in the reaction below are each 0.0355 M. If the initial concentration of I−3 is 0.0 M and the equilibrium constant is Kc=0.25 under certain conditions, what is the equilibrium concentration (in molarity) of I−? I−3(aq)↽−−⇀I2(aq)+I−(aq) Your answer should include two significant figures.

0.032

The initial concentrations of I2 and I− in the reaction below are each 0.0401 M. If the initial concentration of I−3 is 0.0 M and the equilibrium constant is Kc=0.25 under certain conditions, what is the equilibrium concentration (in molarity) of I−? I−3(aq)↽−−⇀I2(aq)+I−(aq)

0.035

The equilibrium constant for the reaction shown below is Kc=2.8567. If the equilibrium concentrations of A and B are 0.0349 M and 0.0427 M, respectively, what is the equilibrium concentration of C? 4A(g)⇌B(g)+3C(g)

0.0463 m

Under certain conditions, the equilibrium constant of the reaction below is Kc=0.25. If the reaction begins with a concentration of 0.0638 M for each of I2 and I− and a concentration of 0.0 M for I−3, what is the equilibrium concentration of I−? I−3(aq)↽−−⇀I2(aq)+I−(aq) Your answer should include two significant figures.

0.053

The equilibrium concentrations of A and B for the reaction below are 0.0055 M and 0.0272 M, respectively. If the equilibrium constant is Kc=0.4708, what is the equilibrium concentration of C? 2A(g)⇌B(g)+3C(g)

0.081 M

Determine the pKb for the base B given that the equilibrium concentrations are [B]=2.64 M, [HB+]=1.5 M, and [OH−]=1.2 M. Report your answer with two decimal places.

0.17

A solution containing 572.0mL of 0.6300MHCl is diluted to a volume of 1.000L. What is the pH of this solution?

0.4433

2A+B↽−−⇀C If equilibrium concentrations are[B]=1.4 Mand[C]=0.85 M, andKc=2.5, what is the equilibrium concentration ofA? Your answer should have two significant figures.

0.49

For the following equilibrium: A+B⇌C+D If the initial concentrations of A and B are 0M each, and the initial concentrations of C and D are 1.6M each, and Kc=4.7, what is the equilibrium concentration of A?

0.51

A solution containing 175mL of 1.50MHBr is diluted to a volume of 1.00L. What is the pH of this solution?

0.581

For the following equilibrium: 2A+B⇌C+2D If equilibrium concentrations are [B]=0.44 M, [C]=0.80 M, and [D]=0.25 M, and Kc=0.22, what is the equilibrium concentration of A?

0.72

he end point in a titration of a 45ml sample of aqueous HCl was reached by addition of 30ml of 0.6M titrant. The titration reaction is 2HCl+Ca(OH)2→CaCl2+2H2O What is the molar concentration ofHCl? Give your answer in one significant figure.

0.8

or the following equation, what is the equation for the reaction quotient? PCl3(l)+Cl2(g)⇌PCl5(s)

1 / [CL2]

The equilibrium constant for the reaction below is 4.0. What is the equilibrium concentration of H2O when a mixture that is 1.4M in H2O, 1.6M in CO, and 1.6M in H2 are mixed to make 1.0L of solution? C(s)+H2O(g)⇌CO(g)+H2(g) Report your answer with two significant figures.

1.0 M

Given the two reactions PbCl2 ⇌ Pb2+ + 2Cl− K3 = 1.72 × 10^−10 and AgCl ⇌ Ag+ + Cl− K4 = 1.29 × 10^−4, what is the equilibrium constant Kfinal for the following reaction? PbCl2 + 2Ag+ ⇌ 2AgCl + Pb2+

1.03 x 10^-2

For the following equilibrium: A+2B⇌C If initial concentrations are [A]=0.50 M, [B]=0.75 M, and [C]=1.2 M, and at equilibrium [C]=1.0 M, what is the equilibrium constant?

1.1

For the following equilibrium: C2H2+2Br2⇌C2H2Br4 If the initial concentrations are: [C2H2]=0.25 M,[Br2]=0.50 M,[C2H2Br4]=2.5 M, and the reaction proceeds in the reverse direction until equilibration, where [C2H2Br4]=2.15 M, what is the final concentration of Br2?

1.2

For the following equilibrium: C2H2+2Br2⇌C2H2Br4 If the initial concentrations are: [C2H2]=0.25 M,[Br2]=0.50 M,[C2H2Br4]=2.5 M, and the reaction proceeds in the reverse direction until equilibration, where [C2H2Br4]=2.15 M, what is the final concentration of Br2?

1.2 M

A solution containing 15.0mL of 4.00MHNO3 is diluted to a volume of 1.00L. What is the pH of the solution?

1.22

What is the hydronium ion concentration in a solution of pH 10.90?

1.3 x 10^-11

The equilibrium constant for the reaction below is 1.0. What is the equilibrium concentration of H2 when a mixture that is 1.2M in C, 1.2M in H2O, 2.1M in CO, and 2.1M in H2 are mixed to make 1.0L of solution? C(s)+H2O(g)⇌CO(g)+H2(g)

1.4

For the following equilibrium: 2A+B⇌2C If initial concentrations are [A]=0.80 M,[B]=0.95 M,[C]=2.5 M, and at equilibrium [C]=1.9 M, what is the equilibrium constant?

1.5

For the following equilibrium: A+B⇌C If equilibrium concentrations are [A]=0.50 M and [B]=0.75 M, and Kc=4.0, what is the equilibrium concentration of C?

1.5

A sample of carbon dioxide in water at room temperature has a hydronium ion concentration of 6.4×10−6 M. What is the hydroxide ion concentration of the solution?

1.6 x 10^-9

Determine the equilibrium concentration of the base NH3 given that pKb=4.76 and the equilibrium concentrations of OH− and NH+4 are 6.5×10−5 M, and 0.42 M respectively.

1.6M

Gaseous hydrogen iodide is placed in a closed container at 425 degrees C, where it partially decomposes to hydrogen and iodine: 2HI(g) ⇌ H2(g) + I2(g). At equilibrium it is found that [HI] = 3.58 × 10^−3 M, [H2] = 4.86 × 10^−4 M , and [I2]= 4.86 × 10^−4 M . What is the value of Kc at this temperature?

1.84 × 10^−2

At a particular temperature, a sample of pure water has a hydronium concentration of 5.4×10−8 M. Which of the following might be the temperature of the sample?

10 degrees celcius

The hydroxide concentration of a solution is equal to:

10-pOH

What is the equilibrium constant for the reversible reaction in aqueous medium below given that the respective concentrations of A, B, C, and D are 0.0117 M, 0.00440 M, 0.00550 M, and 0.00780 M? 3A+3B⇌2C+3D Report your answer with three significant figures.

105

The hydronium concentration of a solution is equal to:

10^-pH

Calculate the hydronium ion concentration of a solution with a pH of −1.07.

12 M

For the reaction below, the concentrations at equilibrium are [SO2]=0.80 M,[O2]=0.25 M, and [SO3]=1.5 M. What is the value of the equilibrium constant, Kc? 2SO2(g)+O2(g)⇌2SO3(g)

14

The reaction A2(g) + B(g) ⇌ A(g) + AB(g) has an equilibrium constant of Kp=2. The accompanying diagram shows a mixture containing A atoms (red - 2 ), A2 molecules (2) , and AB molecules (red and blue - 4). How many B atoms should be added to the diagram to illustrate an equilibrium mixture?

2 atoms

What is the hydroxide concentration in a solution at 25.0∘C with [H3O+]=4.6×10−4 M?

2.2×10−11

At a particular temperature, a sample of pure water has a Kw of 7.7×10−14. What is the hydroxide concentration of this sample?

2.8 x 10^-7

At about 10.∘C, a sample of pure water has a hydronium concentration of 5.4×10−8 M. What is the equilibrium constant, Kw, of water at this temperature?

2.9 x 10^-15

A sample of technetium-99 was used in a procedure to image the heart muscle of a patient 18 hours ago and now 2.50 mCi remain. What was the size of the original sample? (Technetium-99 has a half life of 6 hours.)

20.0 mCi

A mixture initially contains A, B, and C in the following concentrations: [A] = 0.500 M, [B] = 0.700 M, and [C] = 0.500 M. The following reaction occurs and equilibrium is established: A + 2B ⇌ C At equilibrium, [A]= 0.300 M and [C]= 0.700 M. Calculate the value of the equilibrium constant, Kc.

25.9

Consider the following chemical reaction to answer the question that follows. Na2CO3+CaCl2⇌2NaCl+CaCO3 The initial concentrations of CaCl2 and Na2CO3 in a solution are both equal to 0.34 M. After the reaction reaches equilibrium, the concentration of Na2CO3 is 0.05 M. What is the expression for the change in concentration of NaCl?

2x

What are possible algebraic terms representing the relative changes in concentrations for the following reaction? 2SO2+O2↔2SO3

2x, x, −2x

What is the coefficient for O2 in the balanced version of the following chemical equation: C2H4+O2→CO2+H2O

3

Name a secondary alcohol with the formula C5H11OH.

3-pentanol

Hydrogen gas and gaseous iodine will react to form hydrogen iodide, as described by the following chemical equation. H2(g)+I2(g)↽−−⇀2HI(g)Kc(400∘C)=50.0 Assume that all of the HI(g) is removed from a vessel containing this reaction, and equilibrium is re-established. What will be the new equilibrium concentration of HI if the equilibrium concentrations of H2 and I2 are both equal to 0.450M?

3.18

Hydrogen gas and gaseous iodine will react to form hydrogen iodide, as described by the following chemical equation. H2(g)+I2(g)↽−−⇀2HI(g)Kc(400.∘C)=50.0 Assume that all of the HI(g) is removed from a vessel containing this reaction, and equilibrium is re-established. What will be the new equilibrium concentration of HI if the equilibrium concentrations of H2 is 0.450M and I2 is 0.450M?

3.18 M

Determine the Kb for the base B given that the equilibrium concentrations are [B]=2.6 M, [HB+]=0.143 M, and [OH−]=6.2×10−2 M.

3.4 x 10^-3

A solution has a pOH of 9.40 at 50∘C. What is the pH of the solution given that Kw=5.48×10−14 at this temperature?

3.86

What is the pH of a solution with [H3O+]=2.6×10−5 M? Report your answer to the hundredths place.

4.59

For the following equilibrium: 3A+B↽−−⇀2C If equilibrium concentrations are [A]=1.1 M and [B]=1.4 M, and Kc=11.3, what is the equilibrium concentration of C?

4.6

For the following equilibrium: 3A+B↽−−⇀2C If equilibrium concentrations are [A]=1.1 M and [B]=1.4 M, and Kc=11.3, what is the equilibrium concentration of C?

4.6 M

A solution has a pOH of 8.5 at 50∘C. What is the pH of the solution given that Kw=5.48×10−14 at this temperature?

4.8

The initial concentration of acid HA in solution is 0.39 M. If the pH of the solution at equilibrium is 0.76, what is the percent ionization of the acid?

45%

The initial concentration of acid HA in solution is 0.39 M. If the pH of the solution at equilibrium is 0.76, what is the percent ionization of the acid? Remember to use correct significant figures in your answer (round your answer to the nearest whole number). Do not include the percent symbol in your response.

45%

What is the hydroxide ion concentration in a solution of pH 3.71? Remember to report your answer with the correct number of significant figures.

5.1 x 10^-11

At 10∘C, the ion product of water is 2.93×10−15. What is the concentration of hydronium ions at this temperature?

5.41 x 10^-8

A solution has a pH of 7.5 at 50∘C. What is the pOH of the solution given that Kw=8.48×10−14 at this temperature?

5.6

Determine the concentration of hydroxide ions for a 25∘C solution with a pH of 11.75. Your answer should have two significant figures. If reporting your answer in scientific notation form, use the multiplication symbol, ×, not the letter x.

5.6x10^-3

A 10∘C solution has a pH of 8.0. At this temperature, Kw=2.93×10−15. What is the pOH of the solution?

6.5

Initially, a mixture of 0.100 M NO,0.050 M H2,0.100 M H2O was allowed to reach equilibrium (initially there was no N2). At equilibrium the concentration of NO was found to be 0.062 M. Determine the value of the equilibrium constant, Kc, for the reaction: 2NO+2H2↔N2+2H2O

6.5×102

At a certain temperature, the equilibrium constant for the reaction below is 4.55×10−2. Calculate the equilibrium concentration of hydrogen if the equilibrium concentrations of nitrogen and ammonia are 3.98 M and 7.32 M, respectively. N2+3H2⇋2NH3

6.66 M

Ph of an neutral solution

7

Given the two reactions: H2S ⇌ HS− + H+ K1 = 9.44 × 10^−8 and HS− ⇌ S2− + H+ K2 = 1.50 × 10^−19 what is the equilibrium constant Kfinal for the following reaction? S2− + 2H+ ⇌ H2S

7.06 x 10^25

What is the hydroxide ion concentration in a solution of pOH 8.14?

7.2 x 10^-9

What is the Ka for an acid HA, if the equilibrium concentrations are [HA]=1.34 M, [H3O+]=9.89×10−5 M, and [A−]=9.89×10−5 M? Report your answer in scientific notation. Your answer should have three significant figures.

7.30X 10^-9

A solution has a pOH of 7.1 at 10∘C. What is the pH of the solution given that Kw=2.93×10−15 at this temperature? Remember to report your answer with the correct number of significant figures.

7.4

What is the hydroxide ion concentration of a solution at 25∘C with a pH=9.90?

7.9 x 10^-5

A stress on a system can be considered anything that will alter the:

position of the equilibrium

Ph of an basic solution

8-14 (greater than 7)

A solution has an initial concentration of weak acid (HA) equal to 0.150M and has a pH of 1.900 at equilibrium. What is the percent ionization of the acid?

8.4%

Consider the reaction shown below. Before the reaction occurs, the concentrations of A and B are each 0.0280 M. If the concentration of B at equilibrium is 0.0112 M, what is the equilibrium constant? A(g)+B(g)⇌2C(g)

9.00

Which value for Kc indicates an equilibrium that strongly favors products?

981

In a prospective buffer system, as the strength of the weak acid decreases (i.e., as the pKa increases), what happens to the strength of the conjugate base?

???? DEF NOT 'A weak acid has a weak conjugate base.'

Consider the reaction below. According to the Bronsted-Lowry definition, what acts as the conjugate acid when the reaction proceeds in the forward direction? CN−+H2O⇌OH−+HCN

???? DEF NOT H20

Calculate the pH of a solution made with 0.01 M CHES (N-cyclohexyl-2-aminoethanesulfonic acid) and 0.06 M hydrochloric acid. The pKa of CHES is 9.5. Your answer should have two significant figures.

????? DEF NOT 8.8

Identify the options below that are examples of concentrations of reactants affecting the rate of a reaction. (select all that apply) -Calcium reacts at a moderate rate with water to form hydrogen and a base, whereas sodium reacts in a similar way in mere seconds. -A 5 M sample of hydrogen peroxide decomposes at a faster rate than a 2 M sample of the same volume. -Calcium carbonate deteriorates more rapidly in polluted air than in clean air. -Finely ground table salt reacts with sulfur dioxide more quickly than small chunks of salt in a grinder.

A 5 M sample of hydrogen peroxide decomposes at a faster rate than a 2 M sample of the same volume. Calcium carbonate deteriorates more rapidly in polluted air than in clean air.

Lead-212 decays into bismuth-212 by emitting which particle?

A beta particle

Which description best fits the definition of a buffer?

A buffer is a mixture of a weak acid or a weak base and its conjugate.

maintain a relatively constant pH when SMALL AMOUNT OF ACID OR BASE ARE ADDED TO SOLUTION

A buffer solution has the unique property of being able to

when small amount of acid and bases are added -since there is a limit to amount of acid or base that can be added to a buffer solution before it loses its ability to maintain constant pH, this acid or base should be added in small accounts. If the acid or base is added in a large quantity the pH will change dramatically and thus no longer considered a buffer

A buffer solution is able to resist changes in pH

either acid or base -too much acid will use up all conjugate base -too much base will use up all conjugate acid

A buffer solution will exceed its buffer capacity upon the addition of too much:

10% of the conjugate

A buffer solution will lose its buffer capacity when one of the components drops below:

Typically, the rate of a chemical reaction will increase with increasing temperature; however, increasing the temperature of an exothermic reaction will cause the equilibrium to shift toward the reactants. How can a catalyst be used to increase the yield of products at low temperatures?

A catalyst increases the rate of reaction, and will cause a system to reach equilibrium more quickly

Which of the following correctly describes how a scintillation counter works?

A material called a scintillator emits light on exposure to ionizing radiation, and the light is further converted to an electrical signal by an optical sensor.

Which of the following demonstrate homogeneous equilibria?

A reaction occurring in a liquid-phase solution A reaction involving exclusively gaseous species A reaction between solutes in liquid solution

Which of the following demonstrate homogeneous equilibria? (select all that apply)

A reaction occurring in a liquid-phase solution A reaction involving exclusively gaseous species A reaction between solutes in liquid solution

Which is an example of concentration affecting the rate of reaction?

A reaction slows down as it proceeds.

Of the following, which is a false statement regarding chemical equilibrium?

A reversible reaction means a reaction that is at equilibrium between reactants and products.

Of the following, which is a false statement regarding chemical equilibrium? -All reactions are reversible in theory, but it is not always feasible to produce conditions that lead to any significant formation of reactants from the products. -Some reactions favor the forward direction so much over the reverse direction that they proceed until consuming nearly all of the reactants. -A reversible reaction means a reaction that is at equilibrium between reactants and products. -A reversible reaction that is in a state of equilibrium between reactants and products is running in both the forward and reverse directions at the same rate.

A reversible reaction means a reaction that is at equilibrium between reactants and products.

Which of the following are true statements regarding reversible reactions?

A reversible reaction might proceed in only one direction, with negligible contribution from the reverse reaction, depending on conditions. The forward and reverse reactions may occur simultaneously.

basic

A solution that has a greater hydroxide concentration than hydronium concentration will be:

Ph paper

A substance we can use to estimate the measure of ph

low kb and low pOH

A weak base has

The pH of a solution is equal to: A) -log[H3O+] B) log[H3O+] C) -log[OH−] D) log[OH−]

A) -log[H3O+]

A mixture of 0.10 mol of NO, 0.050 mol of H2, and 0.10 mol of H2O is placed in a 1.0-L vessel at 300 K. The following equilibrium is established: 2NO(g) + 2H2(g) ⇌ N2(g) + 2H2O(g) At equilibrium [NO]=0.062M. A) Calculate the equilibrium concentration of H2. B) Calculate the equilibrium concentration of N2. C) Calculate the equilibrium concentration of H2O. D) Calculate Kc.

A) 1.2 x 10^-2 M B) 1.9 x 10^-2 M C) 0.138 M D) 650

At 2000 ∘C the equilibrium constant for the reaction 2NO(g) ⇌ N2(g) + O2(g) is Kc = 2.4×10^3. A) If the initial concentration of NO is 0.171 M, what is the equilibrium concentration of NO? B) If the initial concentration of NO is 0.171 M, what is the equilibrium concentration of N2? C) If the initial concentration of NO is 0.171 M, what is the equilibrium concentration of O2?

A) 1.7 x 10^-3 M B) 8.5 x 10^-2 M C) 8.5 x 10^-2 M

The initial concentration of base B in solution is 0.24 M. If the pH of the solution at equilibrium is 12.53, what is the percent ionization of the base? A) 14.1% B) 20.5% C) 0.71% D) −1.0%

A) 14.1%

H2SO4(aq)+Mg(OH)2(aq)→ __________ + __________ A) 2H2O and MgSO4 B) H2O and MgSO4 C) 2H2O and 2MgSO4 D) 2H2 and MgSO4

A) 2H2O and MgSO4

The K of the reaction: NO2(g) + NO3(g) ⇌ N2O5(g) is K = 2.1 × 10^−20. A) What can be said about this reaction? B) Where does the equilibrium of this reaction lie?

A) At equilibrium the concentration of reactants is much greater than that of products. B) to the left

When the reaction below is going in the forward direction, which compound acts as the base, according to the Bronsted-Lowry definition? PH+4+H2O↽−−⇀PH3+H3O+ A) H2O B) PH+4 C) H3O+ D) PH3

A) H2O

Choose the option below that is a base ionization reaction. A) H2O+HS−↽−−⇀H2S+OH− B) H2O+HF↽−−⇀F−+H3O+ C) PH+4+H2O↽−−⇀PH3+H3O+ D) H2O+HSO−4↽−−⇀SO2−4+H3O+

A) H2O+HS−↽−−⇀H2S+OH− Base ionization involves the transfer of a proton from water to a base to produce hydroxide ions, or the direct release of hydroxide ions into solution from a metal hydroxide salt.

A) Write the expression for Kc for the following reaction: 2Ag(s) + Zn2+(aq) ⇌ 2Ag+(aq) + Zn(s) B) Indicate whether the reaction is homogeneous or heterogeneous.

A) Kc = [Ag+]^2 / [Zn2+] B) heterogeneous

A) Write the expression for Kc for the following reaction: Ni(CO)4(g) ⇌ Ni(s) + 4CO(g) B) Indicate whether the reaction is homogeneous or heterogeneous.

A) Kc = [CO]^4 / [Ni(CO)4] B) heterogeneous

A) Write the expression for Kc for the following reaction: CH4(g) + 2H2S(g) ⇌ CS2(g) + 4H2(g) B) Indicate whether the reaction is homogeneous or heterogeneous.

A) Kc = [CS2][H2]^4 / [CH4][H2S]^2 B) homogeneous

A) Write the expression for Kc for the following reaction: HF(aq) ⇌ H+(aq) + F−(aq) B) Indicate whether the reaction is homogeneous or heterogeneous.

A) Kc = [H+][F-] / [HF] B) homogeneous

A) Write the expression for Kc for the following reaction: 3NO(g) ⇌ N2O(g) + NO2(g) B) Indicate whether the reaction is homogeneous or heterogeneous.

A) Kc = [N2O][NO2] / [NO]^3 B) homogeneous

If we add acid to a buffer containing NaCH3CH2COO and CH3CH2COOH, the acid will react with which of the following? A) NaCH3CH2COO B) CH3CH2COOH C) Na+ D) No reaction will occur.

A) NaCH3CH2COO

If acid HX is stronger than acid HY, which statements are true? Select all that apply. A) The Ka of HX is greater than the Ka of HY. B) The Ka of HX is less than the Ka of HY. C) The [H3O+] in the HX solution is smaller than in the HY solution. D) More of the HX is ionized compared to the HY.

A) The Ka of HX is greater than the Ka of HY. D) More of the HX is ionized compared to the HY.

Which of the following is a true statement about the Lewis definition of acids and bases? A) The Lewis definition of acids and bases is based on donating or accepting an electron pair. B) The Lewis definition of acids and bases is based on the production of H3O+ or OH− ions in water solutions. C) The Lewis definition of acids and bases is based on donating or accepting a proton. D) none of the above

A) The Lewis definition of acids and bases is based on donating or accepting an electron pair.

Which of the following is true of water in a base ionization reaction? A) Water loses a proton and is acting as an acid. B) Water loses a proton and is acting as a base. C) Water accepts a proton and is acting as an acid. D) Water accepts a proton and is acting as a base.

A) Water loses a proton and is acting as an acid.

A Bronsted-Lowry base is best described as __________. A) a proton acceptor B) an electron pair donor C) a base capable of accepting exactly two protons D) a base capable of accepting exactly one proton

A) a proton acceptor

If coffee has a [H3O+] of 10−5 M and an [OH−] of 10−9 M, it is: A) acidic B) basic C) neutral D) depends on the temperature

A) acidic

What is the formula for the conjugate acid of acetate, CH3COO−? A) CH3COO B) CH3COOH C) CH2COO2− D) CH3COOH−

B) CH3COOH

In the earliest of the models to be developed, an acid is defined as something that __________. A) dissolves in water to yield solvated protons, called hydronium ions B) dissolves in water to yield hydroxide ions C) dissolves in water and will produce no ions D) will not dissolve in water

A) dissolves in water to yield solvated protons, called hydronium ions In the Arrhenius model, it is the production of hydronium in water that characterizes an acid.

A) Based on the shown energy profile, predict whether kf > kr or kf < kr. B) Using the equation kf/kr = the equilibrium constant, predict whether the equilibrium constant for the process is greater than 1 or less than 1.

A) kf > kr B) greater than 1

Methanol (CH3OH) can be made by the reaction of CO with H2: CO(g) + 2H2(g) ⇌ CH3OH(g) A) The enthalpy change for the reaction is -90.7 kJ. To maximize the equilibrium yield of methanol, would you use a high or low temperature? B) To maximize the equilibrium yield of methanol, would you use a high or low pressure?

A) low temperature B) high pressure

The reaction 2HCl(aq)+Mg(OH)2(aq)→2H2O(l)+Mg(Cl)2(aq) is an example of what type of reaction? A) neutralization B) dissociation C) oxidation of metals by acid other than water D) reaction of a base with a metal

A) neutralization

The equilibrium constant for the reaction: 2NO(g) + Br2(g) ⇌ 2NOBr(g) is Kc=1.3×10−2 at 1000 K A) At this temperature does the equilibrium favor NO and Br2, or does it favor NOBr? B) Calculate Kc for 2NOBr(g) ⇌ 2NO(g) + Br2(g) C) Calculate Kc for NOBr(g) ⇌ NO(g) + 1/2Br2(g)

A) the equilibrium favor NO and Br2 B) 77 C) 8.8

Acids loose an H+

A-CB

Which substance has a pH that is higher than pure water?

AMMONIA

Neutralization

Acid+ base> salt + water Ex: NaOH+ HCl> NaCl + H2O

Acid- Bronsted-Lowry

Acids are proton donors

2H2S can react to yield 2H2 and S2. Which of the following changes will shift the equilibrium to reactants? (select all that apply)

Add more H2. Add more S2.

Which of the following is a characteristic of aldehydes?

Aldehydes contain an oxygen atom. The carbonyl group in an aldehyde must be attached to a hydrogen atom.

An equilibrium constant is described by which of the following?

An equilibrium constant is the value of the reaction quotient for a system at equilibrium.

less acidic

As metal hydrates deprotonate, they become:

Kw increase cause more OH- & H3O+

As temperature increase

In a sample buffer solution, as the strength of the weak base decreases (i.e., as the pKb increases), what happens to the strength of the conjugate acid?

As the strength of the base decreases, the conjugate acid increases in strength.

5.41x10^-8

At 10∘C, the ion product of water is 2.93×10−15. What is the concentration of hydronium ions at this temperature?

Just before one of the components of buffer is used up

At which point will the pH of a buffered solution begin to change significantly?

Which of the following best indicates the meaning of the term autoionization?

Autoionization is a reaction between two molecules of the same neutral substance to produce an ion pair.

Choose the Ka value that corresponds to the strongest acid. A) 7.4×10−7 B) 0.045 C) 1.7×10−5 D) 6.4×10−8

B) 0.045

During the formation of sodium acetate, NaCH3CO2 , which of the following is are true?1. A solution of the salt NaCH3CO2 contains sodium ions and acetate ions.2. The sodium ion is neither an acid nor a base and thus has no effect on the acidity of the solution.3. The acetate ion, the conjugate base of acetic acid, reacts with water and increases the concentration of the hydroxide ion.4. The acetate ion, the conjugate base of acetic acid, reacts with water and decreases the concentration of the hydroxide ion. A) 1, 2, 4 B) 1, 2, 3 C) 2, 3, 4 D) 1, 3, 4

B) 1, 2, 3

What is the hydronium ion concentration in an aqueous solution with a hydroxide ion concentration of 0.001 M at 25∘C? A) 1×10−8 M B) 1×10−11 M C) 1×10−12 M D) 1×10−14 M

B) 1×10−11 M

Water's pH and pOH are both 7 at: A) 0∘C B) 25∘C C) 100∘C D) any temperature

B) 25∘C

In what ratio will nitric acid and magnesium hydroxide react in a neutralization reaction? HNO3+Mg(OH)2⟶H2O+Mg(NO3)2 A) 1:2 B) 2:1 C) 1:3 D) 3:1

B) 2:1

The Kb of NH3 is 1.8×10−5. What is the Ka of NH+4, its conjugate acid? A) 1.8×10−5 B) 5.6×10−10 C) 1.8×10−19 D) 3.2×10−10

B) 5.6×10−10

Of the following, which are characteristics of basic solutions? (Select all that apply) A) pH levels less than 7 at 25∘C B) Greater concentration of hydroxide ions than hydronium ions C) [H3O+]<[OH−] D) pH levels of 7 at 25∘C

B) Greater concentration of hydroxide ions than hydronium ions C) [H3O+]<[OH−]

In the following reaction, which species acts as an acid? CO2−3+H2S⇌HCO−3+HS− A) CO2−3 B) H2S C) HCO−3 D) HS−

B) H2S

Which of the following acids can be found in the human body? A) HF B) HCl C) HNO3 D) H2SO4

B) HCl

According to the Bronsted-Lowry definition, what is the conjugate base when the reaction below proceeds in the forward direction? H2PO−4+H2O⇌H3O++HPO2−4 A) H2O B) HPO2−4 C) H2PO−4 D) H3O+

B) HPO2−4

A solution of a compound in water conducts electricity, turns litmus blue, and has a bitter taste. What compound might be in the solution? A) HF B) Mg(OH)2 C) C3H5(COOH)3 D) H2SO4

B) Mg(OH)2

Consider the reaction of acetic acid CH3CO2H and water. CH3CO2H(aq)+H2O(l)↽−−⇀CH3CO−2(aq)+H3O+(aq) This equation describes the transfer of hydrogen ions, or protons, between the two substances. Which of the following statements about this process is true? A) Proton transfer will continue until equilibrium is reached. B) Proton transfer will continue indefinitely. C) Proton transfer only procedes in one direction. D) None of the above.

B) Proton transfer will continue indefinitely.

Identify which of following is a base. A) HF B) RbOH C) H2SO4 D) HCO2H

B) RbOH

In the reaction: NaOH⇌Na++OH− where the concentrations for NaOH, Na+, and OH− are each equal to 0.1 M, what is the equation for Kw when finding [H3O+]? A) [0.1 M][0.1 M] B) [H3O+][0.1M] C) [H3O+]/[0.1M] D) [0.1 M]/[H3O+]

B) [H3O+][0.1M]

The equation below is an example of which of the following? CH3COOH+H2O↽−−⇀H3O++CH3COO− A) autoionization B) acid ionization C) base ionization

B) acid ionization

When a base is dissolved in aqueous solution, water is acting as: A) a base. B) an acid. C) both an acid and a base. D) neither an acid nor a base.

B) an acid.

The hydronium ion concentration of vinegar is approximately 4×10−3 M. What are the corresponding values of pOH and pH? A) pH = 0.3, pOH = 13.7 B) pH = 2.4, pOH = 11.6 C) pH = 4.7, pOH = 9.3 D) pH = 6.1, pOH = 7.9

B) pH = 2.4, pOH = 11.6 First we calculate the pH using the given hydronium ion concentration of vinegar (4×10−3 M): pH=−log[H3O+]=-log 4×10−3pH=−(−2.3979)=2.3979 Then we use the pH to calculate the pOH: pH+pOH=14.00 pOH=14.00−pH pOH=14.00−2.3979 pOH=11.6

Identify the option below that is a characteristic of acidic solutions. A) [H3O+]<[OH−] B) pOH levels greater than 7 at 25∘C C) pOH levels less than 7 at 25∘C D) pOH levels of 7 at 25∘C

B) pOH levels greater than 7 at 25∘C Acidic solutions have a greater concentration of hydronium ions, H3O+, than hydroxide ions, OH−. The pH level of an acidic solution is less than 7 at 25∘C and the pOH level is greater than 7 at 25∘C.

Bases gain an H+

B-CA

Base-Bronsted-Lowry

Bases are proton acceptors

the greater the Ka for an acid, the lower the Kb of its conjugate base

Because Kw is a constant:

CH3NH2 and CH3NH3Cl Methylamine (CH3NH2) is an organic base. In order to produce a basic buffer solution similar to blood, we can combine this base with a soluble salt of its conjugate acid, such as CH3NH3Cl. The solution of KOH and H2O would not be a good buffer because KOH is a strong base. The solution of HF and NaF is a buffer, but the pKa of HF is about 3.2, which is far from the pH of blood, 7.4.

Blood is an example of a basic buffer system. Which of the following could be used to mimic the buffering abilities of blood? HF and NaF CH3NH2 and CH3NH3Cl KOH and H2O none of the above

The hydroxide concentration of a solution is equal to: A) −log^pOH B) log^pOH C) 10^−pOH D) 10^pOH

C) 10^−pOH pOH is defined as the negative logarithm of the hydroxide anion concentration (analogous to pH and the hydronium ion concentration), or pOH=−log[OH−]. Use this equation to solve for [OH−]. pOH−pOH[OH−]=−log[OH−]=log[OH−]=10^−pOHRewrite the logarithm as an exponential.

If H2PO−4 participates in an acid ionization, it will generate

HPO4 2-

At 10∘C, the ion product of water is 2.93×10−15. What is the concentration of hydronium ions at this temperature? A) 1.46×10−15 M B) 3.84×10−8 M C) 5.41×10−8 M D) There is not enough information.

C) 5.41×10−8 M

At 100∘C, the ion product of water is 5.13×10−13. What is the concentration of hydronium ions at this temperature? A) 2.56×10−13 M B) 5.06×10−7 M C) 7.16×10−7 M D) There is not enough information.

C) 7.16×10−7 M

Which of the following gives the definition of percent ionization? A) Percent ionization is the equilibrium constant for the ionization of a weak acid. B) Percent ionization is the ratio of the concentration of the undissociated acid at equilibrium to its initial concentration times 100%. C) Percent ionization is the ratio of the concentration of the ionized acid at equilibrium to the initial acid concentration times 100%. D) None of the above

C) Percent ionization is the ratio of the concentration of the ionized acid at equilibrium to the initial acid concentration times 100%.

In a buffer solution made of acetic acid and sodium acetate, any base that is added will react primarily with which of the following? A) hydronium B) hydroxide C) acetic acid D) acetate

C) acetic acid

Roughly how many water molecules are ionized at any given time in a sample of room-temperature water? A) one in a thousand B) one in a million C) one in a billion D) one in a trillion

C) one in a billion

When a small amount of a strong acid or a strong base is added to a buffer solution, the pH will: A) decrease if a strong acid is added B) increase if a strong base is added C) remain relatively constant D) it depends on the strength of the acid or base

C) remain relatively constant

For a weak acid dissociating in water, which of the following is true at equilibrium? A) the rate of the forward reaction is greater than the rate of the reverse reaction B) the rate of the reverse reaction is greater than the rate of the forward reaction C) the rates of the forward and reverse reactions will be equal D) depends on the acid

C) the rates of the forward and reverse reactions will be equal

Strong acids are paired with: A) strong conjugate bases. B) water. C) weak conjugate bases. D) weak conjugate acids.

C) weak conjugate bases.

Which of the following is the correct molecular formula for 2,3-dimethyl-1-pentanol?

C7H16O

Which is a possible example of species that can comprise a buffer solution?

CH3COOH and NaCH3COO

Which of the following illustrates how the intrinsic chemical properties of a reactant affect reaction rate? (select all that apply)

Calcium reacts with water at a moderate rate to form hydrogen gas and a base, whereas sodium reacts in a similar way in mere seconds. A wooden headboard burns more quickly in a fire than an iron headboard. Phosphorus burns much more rapidly in an atmosphere of pure oxygen than in air. Zinc dust reacts more rapidly with hydrochloric acid than a large solid piece of zinc.

Universal indicator

Can be made by mixing several different indicator solutions together

H2O+HF↽−−⇀F−+H3O

Choose the option below that is an acid ionization reaction. H2O+HF↽−−⇀F−+H3O+ H2O+NH−2↽−−⇀OH−+NH3 CN−+H2O↽−−⇀OH−+HCN H2O+H2PO−4↽−−⇀H3PO4+OH−

Identify the options below that are false about chemical equilibria. (select all that apply)

Concentrations of products and reactants oscillate between a set range of values. At equilibrium, all species have stopped reacting altogether.

Identify the options below that are false about chemical equilibria.

Concentrations of products and reactants oscillate between a set range of values. At equilibrium, all species have stopped reacting altogether.

Calculate the hydronium ion concentration of a solution with a pH of −1.070. A) 5.1 M B) 7.7 M C) 9.3 M D) 11.7 M

D) 11.7 M

The initial concentration of base B in solution is 0.72 M. If the pH of the solution at equilibrium is 9.4, what is the percent ionization of the base? A) 12% B) 7.2% C) 2.9% D) 3.5×10−3%

D) 3.5×10−3%

Which pOH value corresponds to an acidic solution at room temperature? A) 3.7 B) 5.9 C) 9.2 D) 7

D) 7 If a pH below 7 corresponds to an acidic solution at room temperature, then a pOH above 7 also corresponds to an acidic solution.

What is the conjugate base in the forward reaction? C2O4+HC2H3O2⇌HC2O−4+C2H3O2− A) C2O4 B) HC2H3O2 C) HC2O4− D) C2H3O2−

D) C2H3O2−

What products are formed as a result of the dissolution of solid calcium hydroxide (Ca(OH)2) in water? (Ignore stoichiometry.) A) Ca2+(aq) and H2O(l) B) Ca(s) and H2(g) C) Ca(OH)2−4(aq) and H2(g) D) Ca2+(aq) and OH−(aq)

D) Ca2+(aq) and OH−(aq)

What are the expected products of the unbalanced reaction: HNO3(aq)+Ba(OH)2(aq)→? A) Ba(NO3)2(aq) B) O2(g)+Ba(NO3)2(aq) C) H2(g)+Ba(NO3)2(aq) D) H2O(l)+Ba(NO3)2(aq)

D) H2O(l)+Ba(NO3)2(aq)

In an acid-base reaction involving neutral base B, what will be the conjugate acid? A) H2O B) H3O+ C) OH− D) HB+

D) HB+

Which acid is the strongest when dissolved in water? Ka values are listed next to the acid. A) CH3COOH, Ka=1.8×10−5 B) HNO2, Ka=4.0×10−4 C) HF, Ka=6.8×10−4 D) HClO2, Ka=1.1×10−2

D) HClO2, Ka=1.1×10−2 The larger the Ka value, the stronger the acid, meaning it ionizes to a greater extent. The acid with the largest Ka value is HClO2, which has Ka=1.1×10−2. This means HClO2 is the strongest acid listed.

In a buffer solution made of acetic acid and sodium acetate, if a small amount of acid is added, the added acid will react with which of the following? A) hydronium ions B) sodium ions C) acetic acid D) acetate ions

D) acetate ions

When an acid-base reaction is at equilibrium, the equilibrium constant will be equal to: A) −1 B) 0 C) 1 D) the reaction quotient

D) the reaction quotient

According to the Bronsted-Lowry definition, what acts as the acid when the reaction below proceeds in the forward direction? H2O+HSO−4⇌SO2−4+H3O+

HSO4^-

The lowest value that is possible on the pH scale is: A) 1 B) 0 C) −1 D) there is no fundamental lower limit

D) there is no fundamental lower limit As this is simply the negative log of the hydronium concentration, each pH unit descended is simply an order of magnitude greater for hydronium concentration, so even at −1, which means 10M in hydronium, there is no theoretical limit at this point. That being said, in the real world, the lowest pH observed is approximately −2, and the highest is approximately 16.

Which of the following decreases the rate of a reaction? -Decreasing the concentration of a reactant that does not appear in the rate law -Heating up the reaction vessel on a hot plate -Taking a break after continuously stirring a very slow reaction for half an hour -Decreasing the concentration of a first order reactant

Decreasing the concentration of a first order reactant

What is the the most widely used ether?

Diethyl ether

Equivalence point in a titration

Equivalent amounts of H+ and OH-

Which of the following substances is capable of autoionization?

H2O

Of the following, which is an acid ionization reaction?

H2O+HSO−4↽−−⇀SO2−4+H3O+

Choose the option below that is a base ionization reaction.

H2O+HS−↽−−⇀H2S+OH−

Which of the chemical species in the following reaction is the conjugate base? H3PO4+H2O⟶H2PO−4+H3O+

H2PO−4

What is the formula for sulfuric acid?

H2SO4

Complete the chemical equation for the acid ionization of hydrochloric acid HCl in water.

H30+ / Cl-

Which of the following reactions shows water acting as the conjugate base of an acid?

H3O+ + HPO2−4 ↽−−⇀ H2PO−4 + H2O

Which of the following reactions shows water acting as the conjugate base of an acid?

H3O++HPO2−4↽−−⇀H2PO−4+H2O

Complete and balance the chemical equation for the neutralization reaction of phosphoric acid (H3PO4(aq)) and sodium hydroxide (NaOH(aq)). Write the chemical equation in molecular form (do not show dissociated ions). Include the state (phase) of each chemical species.

H3PO4(aq)+3NaOH(aq)⟶3H2O(l)+Na3PO4(aq)

Consider the equation for the reaction for the acid ionization of H2PO−4. H2PO−4 + H2O ↽⇀ H3O+ + _____ What is the formula for the missing product for this reaction?

HPO2−4.

The Bronsted-Lowry definition of acids and bases refers to the transfer of a "proton" from the acid to the base; however, the symbol for a proton (p+) is not generally used in this context. What is the chemical symbol that is commonly used to represent a "proton" in the context of Bronsted-Lowry acids and bases? Enter a chemical symbol that can be considered equivalent to a single proton.

H^+

Which of the following will NOT participate in an acid ionization reaction?

He

Which of the following best describes the term homogeneous equilibrium?

Homogeneous equilibrium is the equilibrium in a system in which all reactants and products are present in a single phase

Which of the following best describes the term homogeneous equilibrium?

Homogeneous equilibrium is the equilibrium in a system in which all reactants and products are present in a single phase.

What element could be used as fuel in a nuclear fusion reactor?

Hydrogen

high heat capacity high boiling point high capacity for cohesion

Hydrogen bonding in liquid water explains its:

A proton is considered to be...

Hydrogen ion

change more dramatically with the second addition than with the first

If 100mL of a strong bade is added to dilute buffer solution TWICE, the pH of the solution will likely

H2SO3 and OH-

If HSO−3 behaves as a base in water, what will result?

The solution's buffer capacity has not yet been reached.

If a certain amount if strong base is added to a buffer solution with pH of 5.98 and the pH after the addition if the base is 6.02, what can be said about the solution?

The Ka of HX is greater than the Ka of HY. More of the HX is ionized compared to the HY.

If acid HX is stronger than acid HY, which statements are true? Select all that apply. oThe Ka of HX is greater than the Ka of HY. oThe Ka of HX is less than the Ka of HY. oThe [H3O+] in the HX solution is smaller than in the HY solution. oMore of the HX is ionized compared to the HY.

NaCH3CH2COO -H+ ions is dissociated from the acid and will react with the propanoate CH3CH2COO- ions to form more CH3CH2COOH and water, thereby neutralizing the acid with relatively little change in the ph of the solution

If we add acid to a buffer containing NaCH3CH2COO and CH3CH2COOH, the acid will react with which of the following?

weak acid and a salt containing its conjugate base A weak acid and a salt containing its conjugate base will be an ideal system for creating a buffer solution with a pH below 7. A weak base and a salt containing its conjugate acid will create a buffer solution with a pH above 7. A strong base and a salt containing its conjugate acid will not produce a buffer solution.

In order to generate a buffer solution with a pH below 7, what type of substance should be used?

Choose the option below that is true of temperature changes.

Increasing the temperature of an exothermic reaction will cause the system to shift toward the reactants.

Choose the option below that is true of temperature changes.

Increasing the temperature of an exothermic reaction will cause the system to shift toward the reactants. Increasing the temperature of a chemical system increases the internal energy of the system. Unlike changes in concentration and pressure, changes in temperature affect the equilibrium constant. As the temperature changes, the chemical system will absorb or give off heat to relieve the equilibrium disturbance. For exothermic reactions, an increase in temperature shifts the reactions toward the reactants. For endothermic reactions, an increase in temperature shifts the reactions toward the products. The shifts are reversed for decreases in temperature.

Acid-Arrhenius

Produce hydronium ions in ion solution (H3O+)(H+)

Base-Arrhenius

Produce hydroxide ions (OH-) in solution

A reaction quotient is symbolized by the letter:

Q

As a system shifts to alleviate a stress, it will continue to do so until:

Q = K

What is the reaction quotient for the reversible reaction shown below? P4(s)+5O2(g)⇌P4O10(s)

Qc = 1 / [O2]^5

What is the reaction quotient for the reversible reaction shown below?P4(s)+5O2(g)⇌P4O10(s)

Qc = 1 / [O2]^5

Calculate the reaction quotient and determine the direction in which the following reaction will proceed to reach equilibrium. [SO3]=0.28 M,[SO2]=0.12 M, and [O2]=0.040 M2SO3(g)⇌2SO2(g)+O2(g) Kc=0.230

Qc=7.3×10−3 and the reaction will shift right

The ideal gas constant is symbolized as:

R

two in a billion

Roughly how many water molecules are ionized at any given time in a sample of room-temperature water?

Consider the reaction below. H2S+SO2−4⇌HS−+HSO−4 Which of the above chemical species is the Brønsted-Lowry base in the forward reaction?

SO2−4

What is the pH scale?

Scale from 0-14

Sulfuric acid reacts with sodium carbonate to form water, a salt, and a gas. Write the formulas for the salt and other compound that are formed in the reaction. Na2CO3(aq)+H2SO4(aq)⟶H2O(l)+?+?

The formula for sulfuric acid is H2SO4, and the formula for sodium carbonate is Na2CO3. The gas evolved in the reaction of a carbonate with an acid is carbon dioxide, or CO2. Water is also given as one of the products. So part of the reaction will be as shown below. Na2CO3(aq)+H2SO4(aq)⟶CO2(g)+H2O(l)+? The sodium ions and the sulfate ion from the reactants are missing in the products. They must be added. Recall that a sodium ion has a charge of plus one and a sulfate ion has a charge of minus two. The complete reaction is shown below. Na2CO3(aq)+H2SO4(aq)⟶CO2(g)+H2O(l)+Na2SO4(aq) Besides water, the products are CO2 gas and sodium sulfate, Na2SO4.

-The law of mass action best fits which of the following descriptions? -The law of mass action is the statement that a chemical system returns to equilibrium after a disturbance. -The law of mass action is a model that emphasizes the energy and orientation of molecular collisions to explain and predict reaction kinetics. -The law of mass action is the statement that the partial pressure exerted by a solution component is equal to the product of the component's mole fraction in the solution and its equilibrium vapor pressure in the pure state. -The law of mass action is the statement that the reaction quotient remains constant when a reversible reaction has attained equilibrium at a given temperature.

The law of mass action is the statement that the reaction quotient remains constant when a reversible reaction has attained equilibrium at a given temperature.

The law of mass action best fits which of the following descriptions?

The law of mass action is the statement that the reaction quotient remains constant when a reversible reaction has attained equilibrium at a given temperature.

105 degrees

The measure of the bond angle in a water molecule is approximately which of the following?

Which of the following conditions are necessary for a change in total pressure to result in a change to the relative amounts of reactants and products for a gas phase reaction that is at equilibrium?

The pressure change is a result of changing the volume of the container. The number of moles of gas on each side of the reaction are different.

Ammonia can be produced via the chemical reaction N2(g) + 3H2(g) ⇌ 2NH3(g) During the production process, the production engineer determines the reaction quotient to be Q= 3.56×10−4. If K= 6.02×10−2, what can be said about the reaction?

The reaction is not at equilibrium and will proceed to the right.

The industrial production of lime (CaO) from calcium carbonate is accomplished via the following reaction: CaCO3(s) ⇌ CaO(s) + CO2(g) Given the following data: Temperature K 298 1.93 x 10^-23 1200 1.01 what can be said about this reaction?

The reaction makes more lime at higher temperatures.

Which of the following are not results of adding a catalyst to a chemical system at equilibrium? (select all that apply)

The reaction quotient decreases. The equilibrium constant increases.

Identify the options below that are results of adding a catalyst to a chemical system. (select all that apply)

The reaction rates are increased. The reaction quotient is unaffected. The equilibrium constant is unaffected.

Which of the the following will be the result of adding more of a product to a chemical system at equilibrium?

The reaction shifts toward the reactants.

Of the following, which are not results of adding a catalyst to a chemical system at equilibrium?

The reaction shifts toward the reactants. The reaction quotient increases. The equilibrium constant increases.

Now consider the reaction A + 2B ⇌ C for which in the initial mixture Qc= [C] / [A][B]^2 = 387 Is the reaction at equilibrium? If not, in which direction will it proceed to reach equilibrium?

The reaction will proceed in reverse to form reactants.

The reaction 2CH4(g) ⇌ C2H2(g) + 3H2(g) has an equilibrium constant of K= 0.154. If 6.90 mol of CH4, 4.75 mol of C2H2, and 10.55 mol of H2 are added to a reaction vessel with a volume of 5.00 L , what net reaction will occur?

The reaction will proceed to the left to establish equilibrium.

For the following reaction initially at equilibrium, what will occur if the volume of the container is increased? 2SO3(g)⇌2SO2(g)+O2(g)

The reaction will proceed to the right.

Which base is the weakest when dissolved in water? Kb values are listed next to the base. A) PO3−4 Kb=5.9×10−3 B) NH3 Kb=2.8×10−5 C) C6H5NH2 Kb=4.2×10−10 D) N2H4 Kb=9.5×10−7

The smaller the Kb value, the weaker the base, meaning it ionizes to a lesser extent and creates fewer products. The base with the smallest Kb value is C6H5NH2, which has Kb=4.2×10−10. This means C6H5NH2 is the weakest base listed.

Which is an example of the state of subdivision of the reactants affecting the rate of reaction? -The smaller the piece of wood, the faster it burns -Food spoils more quickly on the kitchen counter than in the fridge -A reaction slows down as it proceeds -Calcium reacts with water moderately, sodium reacts with water explosively

The smaller the piece of wood, the faster it burns (The smaller pieces of wood have greater surface area available for combustion and thus the rate of reaction is influenced by subdivision. The rate of reaction in the other examples are influenced by temperature (choice b), concentration (choice c), and chemical nature (choice d).

Of the following, which is not a result of adding more of a reactant to a chemical system at equilibrium?

The value of K increases.

A small amount of reactant is removed from a system at equilibrium. Which of the following will change?

The value of Q

Since we are told that the ratio of the acid (HA) to its conjugate base (A−) is 5:1, we do not actually need to know their concentration values: suffice it to say that [A−][HA] is 15. This simplifies the equation to the following, plugging in the given value of pKa as well: pH=6.1+log(15) Solving this shows that pH=5.4.

What will be the pH of a buffer solution containing an acid of pKa6.1, with an acid concentration exactly five times that of the conjugate base?

pH=pKa+log[A−][HA] pH=2.9+log(10)=3.9

What will be the pH of a buffer solution with an acid (pKa2.9) whose concentration is exactly 10.% that of its conjugate base?

hydrated

When a metal ion is interacting with as many water molecules as possible, we say that it is:

Qc at equilibrium =Kc illustrates the law of mass action, which states:

When a reaction has attained equilibrium at a given temperature, the reaction quotient for the reaction always has the same value.

conjugate base of the weak acid and its usually weak base

When a weak acid is combined with strong base, the salt that forms contains the

unionized base If a base is weak, it will only be protonated to a very small extent, forming its conjugate acid and hydroxide in only negligible amounts relative to the concentration of unprotonated base.

When a weak base is placed in aqueous solution, which of the following will be present in the greatest concentration?

A metal and an acid react violently to form sodium sulfate and hydrogen gas. What are the acid and the metal? Write chemical formulas separated by a comma. Do not include the state of matter of the species in your answers.

When an acid oxidizes a metal, the products are hydrogen gas and a salt that consists of a cation of the metal and the anion of the acid. The formula for sodium sulfate is Na2SO4, because the sodium ion has a charge of +1 and the sulfate ion has a charge of −2. Therefore, the metal will be elemental sodium, Na, and the acid will be sulfuric acid, H2SO4. The equation of the very explosive reaction is shown below. 2Na(s)+H2SO4(aq)⟶Na2SO4(aq)+H2(g)

Identify the option below that exemplifies how the intrinsic chemical properties of a reactant affect the rate of reaction.

When exposed to air, sodium reacts completely overnight, whereas iron barely reacts.

What is the end point in a titration

When the indicator changes color

the rates of the forward and reverse reactions will be equal

When the ionization reaction of a weak base is at equilibrium,

A chemical reaction is at equilibrium. In which of the following circumstances would a change in temperature be least likely to affect the equilibrium of a chemical reaction?

When there is no change in enthalpy between the reactants and the products.

base ionization reaction occurs in which protons are transferred from water molecules to base molecules

When we add a base to water

conjugate acid It is the conjugate acid of the weak base that generates hydronium and therefore contributes to the pH.

When we react a weak base with a strong acid, the component of the base that contributes to the pH of the solution is the:

1.0M NH3 + 1.0 M NH4+

Which buffer will have the greatest buffer capacity? •1.0M NH3 + 1.0 M NH4+ •0.5M NH3 + 0.5 M NH4+ •0.3M NH3 + 0.3 M NH4+ •0.1M NH3 + 0.1 M NH4+

A buffer is a mixture of weak acid or weak base and its conjugate.

Which description best fits the definition of a buffer?

CH3COOH & NaCH3COO -made up of weak acid and conjugate base

Which is possible example if species that can comprise a buffer solution? •CH3COOH & NaCH3COO •CH3OH & CH3COOH •HCl & NaOH •H2O & NaOH

carbonic acid

Which is the acid responsible for the buffering capacity of blood?

-Liquid water has a high level of cohesion. -Water molecules can form multiple hydrogen bonds.

Which of the following are characteristics of water?

Living cells have a tendency to burst when they freeze. Ice forms on the surface of bodies of water and remains there, insulating the water below from the cold.

Which of the following are consequences of water expanding when it freezes? •Living cells have a tendency to burst when they freeze. •Hydrogen bonds break when water goes from a liquid to a solid state. •Ice forms on the surface of bodies of water and remains there, insulating the water below from the cold. •The bond angle in water changes from 105∘ to 120∘

Because the molecule is bent, the central oxygen, which is more electronegative, can be on one side, and the two hydrogens, which are less electronegative, can be on the other.

Which of the following is the reason for the polarity of the water molecule?

Amphiprotic

Which of the following is the term for a species that may either gain or lose a proton under appropriate conditions?

The solution with greater concentration will have greater buffer capacity

Which of the following is true of two 100 solutions, each with a pH of 4.83 and identical ratlos buffering species but with one more dilute than the other

Water loses a proton and is acting as an acid.

Which of the following is true of water in a base ionization reaction?

H3O++HPO2−4↽−−⇀H2PO−4+H2O

Which of the following reactions shows water acting as the conjugate base of an acid? H2O+CO2↽−−⇀H2CO3 H2S+OH−↽−−⇀H2O+HS− H3O++HPO2−4↽−−⇀H2PO−4+H2O CN−+H2O↽−−⇀OH−+HCN

The pH of the solution is impossible to determine without more information. If both the acid and base are weak, it is impossible to predict the acidity of the resulting solution without knowing the identities and relative amounts of the acid and the base in the solution.

Which of the following will be true if a equal amounts of an unknown weak acid and an unknown weak base are mixed with water? The solution will have a pH>7 The solution will have a pH<7 The solution will have a pH=7 The pH of the solution is impossible to determine without more information.

a unbuffered aqueous solution -solutions containing ammonia and ammonium chloride are buffered and can resist changes in pH, whereas the unbuffered solutions cannot. ammonia solution will be able to neutralized some acid before having its pH lowered, but the water in aqueous solution will immediately react with acid to form hydronium ions, thus affecting the pH the most

Which of the following will exhibit the greatest change in pH when 1.0 mL of 1 M HCl is added to it?

strong acid

Which species would increase the concentration of hydronium in solution the most?

strong base

Which species would increase the concentration of hydroxide in solution the most?

NaHCO3 -from NaOH (Strong base) and H2CO3 (Weak acid)

Which will form a salt from a strong base and weak acid

It will react with water. -because acid is weak, conjugate base is somewhat strong which will react with water molecules to produce hydroxide affecting ph solution

Why will the conjugate base of a weak acid affect pH?

H2O(l)+H2O(l)↽−−⇀H3O++OH-

Write the chemical equation for the autoionization of water.

Acetic acid, CH3CO2H, reacts with ethanol, C2H5OH, to form ethyl acetate, CH3CO2C2H5 and water. CH3CO2H+C2H5OH↽−−⇀CH3CO2C2H5+H2O The equilibrium constant for this reaction with dioxane as a solvent is 4.0. What are the equilibrium concentrations when a mixture that is 0.15 M in CH3CO2H,0.15 M in C2H5OH,0.40 M in CH3CO2C2H5, and 0.40 M in H2O are mixed in enough dioxane to make 1.0 L of solution?

[CH3CO2H] = 0.18 M, [C2H5OH] = 0.18 M, [CH3CO2C2H5] = 0.37 M, [H2O] = 0.37 M

Find the reaction quotient for the reversible reaction below. 2CO2(g)⇌2CO(g)+O2(g)

[CO]^2[O2] / [CO2]^2

Find the reaction quotient for the reversible reaction below.2CO2(g)⇌2CO(g)+O2(g)

[CO]^2[O2] / [CO2]^2

Under certain conditions, the equilibrium constant for the following equation is 6.0. H2+I2↽−−⇀2HI What are the equilibrium concentrations of H2,l2, and HI if the initial concentration of HI was 4.0 M and the initial concentrations of both H2 and l2 are zero?

[H2]=0.90 M,[I2]=0.90 M,[HI]=2.2 M

Percent ionization for an aqueous acid can be expressed as:

[H3O+]eq / [HA]i×100%, where "eq" stands for equilibrium and "i" stands for initial

Write the expression for the reaction quotient in terms of concentration for the following reaction. 3H2+N2↽−−⇀2NH3

[NH3]^2 / [N2][H2]^3

Write the expression for the reaction quotient in terms of concentration for the following reaction.3H2+N2↽−−⇀2NH3

[NH3]^2 / [N2][H2]^3

Given the reaction below, what is the reaction quotient? 2KClO3(s)⇌2KCl(s)+3O2(g)

[O2]^3

Given the reaction below, what is the reaction quotient? 2KClO3(s)⇌2KCl(s)+3O2(g) Write the expression in terms of the concentration(s) of the species.

[O2]^3

Which of the following is true of water in a base ionization reaction? a. Water loses a proton and is acting as an acid b. Water loses a proton and is acting as a base c. Water accepts a proton and is acting as an acid d. Water accepts a proton and is acting as a base

a

Which of the following will affect equilibrium constant of a reaction?

a change in temperature

Which of the following will affect equilibrium constant of a reaction?

a change in temperature A change in temperature will affect the equilibrium constant, which is what causes the equilibrium to shift, so that the equilibrium concentrations can reflect the new value for Kc. Changing pressure or a particular concentration may shift the direction of a reaction, but do not change the value of the equilibrium constant itself.

An ICE chart is needed to calculate Kc if:

a combination of initial concentrations and at least one equilibrium concentration are given

Which will cause the following equilibrium to shift to the right? 2H2(g)+S2(g)⇌2H2S(g)

a decrease in the volume of the vessel in which the reaction is contained

1.0 mL of 0.1M NaOH is added to 100 mL of several solutions. Which of the following was most likely a buffered solution?

a solution whose pH changed from 4.97 to 5.08

A buffer is a mixture of:

a weak acid or base and its conjugate

In a buffer solution made of acetic acid and sodium acetate, if a small amount of acid is added, the added acid will react with which of the following?

acetate ions

Which of the following shows the correct order of the components in the equation below? HF+H2O↽−−⇀H3O++F−

acid + base ↽−−⇀ acid + base

ethanol can be synthesized from ethylene and water, using:

acid catalysis

The equation below is an example of which of the following? CH3COOH+H2O↽−−⇀H3O++CH3COO−

acid ionization

A buffer solution in which the Ka of the acid is greater than the Kb of the conjugate base will be _______________.

acidic

Shown below is the formation reaction of ammonia. How does the catalyst used in the industrial production of ammonia affect the activation energies of the forward and reverse reactions? N2+3H2⇌2NH3

activation energy decreased both the forward and reverse reactions

Use the following equation as a guide to complete the sentence below. The initial concentration of PCl5 is 1.00 M. PCl5⇋PCl3+Cl2 To find the equilibrium concentrations for each product from the ICE chart, _______________.

add the initial concentration of the product and the change in concentration

Radioactive tracers are used in _______________. Select the correct answer below: medical applications analyzing the geological formation around oil wells tracking engine wear all of the above

all of the above

Radiometric dating has been responsible for breakthrough discoveries in: Select the correct answer below: geology biology anthropology all of the above

all of the above

Which of the following alcohols is a liquid at room temperature? ethanol butanol methanol all of the above

all of the above

Which of the following is included in a nuclide symbol?

all of the above

A system at equilibrium has two aqueous products and two aqueous reactants. An additional amount of one of the products is added to the system. After the addition of one product, which of the following will change?

all of the above (- the concentration of the added product - the concentration of the other product - the concentrations of the reactants)

For the following equilibrium: N2+3H2→2NH3change in enthalpy=−92.2 kJ The presence of catalyst is necessary to best optimize the:

all of the above (rate,yield, cost efficiency) A catalyst will optimize the yield of the equilibrium, the rate at which ammonia is produced, and the cost efficiency of the process.

Which of the following will exhibit the greatest change in pH when 1.0 mL of 1.5M NaOH is added to it?

an unbuffered aqueous solution that is 0.10M in NaCH3COO

Catalysts are typically in the:

any phase

The equilibrium constant is equal to the reaction quotient when the system is:

at equilibrium

Ba(OH)2

barium hydroxide (strong base)

A buffer solution in which the Kb of the base is greater than the Ka of the conjugate acid will be _______________.

basic

A reaction that produces ammonia is shown below. How does the catalyst used in the industrial production of ammonia affect the reaction rates of the forward and reverse reactions? N2+3H2⇌2NH3

both the forward and reverse rates increase

A reaction that produces ammonia is shown below. How does the catalyst used in the industrial production of ammonia affect the reaction rates of the forward and reverse reactions? N2+3H2⇌2NH3

both the forward and reverse rates increase Catalysts increase the reaction rates for both the forward and reverse reactions.

Which of the following is best described as a proton acceptor?

bronsted-Lowry base

An increase in temperature will cause an equilibrium to:

depends on the equilibrium

When propanone is reduced, the double bond between the carbon and oxygen becomes a single bond and hydrogen atoms are added to:

carbon and oxygen

Identify the product(s) that form when an aldehyde undergoes incomplete combustion.

carbon monoxide

CsOH

cesium hydroxide (strong base)

In an ICE chart, the C stands for:

change

When calculating changes in concentration, the algebraic terms calculated from the stoichiometry of the equilibrium equation will go into which row of an ICE chart?

change

Changing the temperature of a system at equilibrium

changes the value of the equilibrium constant

Changing the temperature of a system at equilibrium:

changes the value of the equilibrium constant

Changing the temperature of a system at equilibrium: -shifts the reaction quotient away from the equilibrium value -increases the rate of reaction -changes the value of the equilibrium constant -it depends on the equation

changes the value of the equilibrium constant

Chemical equilibria, particularly those that involve components in the gas phase, often require that a reaction vessel be:

closed, If a reaction takes place in an open vessel, products might escape into the atmosphere, which would make it impossible for the reverse reaction to occur.

Any compound that is more acidic than the hydronium ion will undergo what type of ionization?

complete ionization

If Q is followed by a subscript c, that means it is evaluated using:

concentration

If K is followed by a subscript c, that means it is evaluated using:

concentrations

Identify the option below that is an acid ionization reaction a. H2O + NH−2 ↽⇀ OH− + NH3 b. H2O + H2PO−4 ↽⇀ H3PO4 + OH− c. CN− + H2O ↽⇀ OH− + HCN d. PH+4 + H2O ↽⇀ PH3+ H3O+

d

Which of the following will NOT participate in an acid ionization reaction? a. HCl b. H2O c. HBr d. He

d (In order to participate in an acid ionization, a substance must be able to donate or accept a proton. Helium can do neither)

Based on the reaction below, how will the concentration of D change if the concentration of C decreases by 0.053 M? 2A(aq)+5B(aq)⇋5C(aq)+D(aq)

decreases by .011 M

Which of the following has the potential to change the equilibrium in a reaction involving gases? Select all that apply.

decreasing the volume of the system to half of its original value increasing the volume of the system to twice its original value doubling the amount of one of the components in the system doubling the amount of all of the components in the system

K is always __________.

dependent on the reaction

Q is always

dependent on the reaction and its progress.

Q is always __________.

dependent on the reaction and its progress.

The catalyst used in the industrial production of ammonia:

enables equilibrium to be reached more quickly

The catalyst used in the industrial production of ammonia:

enables equilibrium to be reached more quickly The net effect of the catalyst used in the industrial production of ammonia is a more rapid achievement of equilibrium.

The direction an equilibrium shifts after experiencing a change in temperature will depend on what parameter for the system?

enthalpy

A chemical reaction is at equilibrium. In which of the following circumstances would a change in temperature be least likely to affect the equilibrium of a chemical reaction? rate of the forward reaction rate of the reverse reaction equilbrium constant none of the above

equilbrium constant A change in temperature will affect the equilibrium constant, which is what causes the equilibrium to shift, so that the equilibrium concentrations can reflect the new value for Kc

An equilibrium constant can be calculated if only the ____________

equilibrium concentrations are known.

All acid-ionization reactions and base-ionization reactions are __________

equilibrium processes

The formation of ammonia from nitrogen and hydrogen is a(an) _________ process.

exothermic

The formation of ammonia from nitrogen and hydrogen is a(an) _________ process.

exothermic The formation of ammonia from nitrogen and hydrogen is an exothermic process as heat will be released in this reaction moving from reactants to products.

An unbuffered solution _______.

fails to keep hydronium and hydroxide ion concentrations nearly constant when strong acids or bases are added

If Q is less than K, in which direction will the equilibrium proceed?

forward

A change in pressure will have an effect on:

gaseous equilibria

A catalyst will: -increase the change in enthalpy of a reaction -decrease the change in enthalpy of a reaction -have no effect on the change in enthalpy of a reaction -depends on the reaction

have no effect on the change in enthalpy of a reaction A catalyst only affects the energy of the transition state, it will have no impact on the change in enthalpy for the overall reaction.

Which type of equilibrium is more likely to omit substances from the equilibrium constant expression?

heterogeneous equilibria

HBr (aq)

hydrobromic acid (strong acid)

HCl (aq)

hydrochloric acid (strong acid)

Which of the following is NOT a strong acid?

hydrofluoric acid

HI (aq)

hydroiodic acid (strong acid)

An aqueous acid ionization reaction always generates

hydronium

An aqueous base ionization reaction always generates

hydroxide

As a reaction proceeds in the forward direction, K will:

increase

As a reaction proceeds in the forward direction, Q will

increase

As a reaction proceeds in the forward direction, Q will:

increase

For the following equilibrium: N2+3H2→2NH3change in enthalpy=−92.2 kJ The presence of catalyst speeds up the forward reaction which is most likely to be favored when there is:

increased pressure

For the following equilibrium: N2+3H2→2NH3change in enthalpy=−92.2 kJ The presence of catalyst speeds up the forward reaction which is most likely to be favored when there is:

increased pressure If the pressure increases, the forward reaction will speed up, since there are fewer moles of particles on the right. A catalyst will increase the rate of the forward reaction.

Consider the following system at equilibrium: 3A(aq) + 3B(aq) ⇌ 5C(aq) Classify each of the following actions by whether it causes a leftward shift, a rightward shift, or no shift in the direction of the net reaction.

leftward shift -increase [C] -decrease [A] -decrease [B] -double both [B] and [C] rightward shift -increase [A] -increase [B] -decrease [C] no shift -double [A] and reduce [B] to one half

For a certain chemical reaction, ΔH degrees = −156 kJ. Assuming the reaction is at equilibrium, classify each of the following actions by whether it causes a leftward shift, a rightward shift, or no shift in the direction of the net reaction.

leftward shift -increase the temperature rightward shift -decrease the temperature no shift N/A

The following system is at equilibrium: X(s) + 3Y(g) ⇌ Z(g) Classify each of the following actions by whether it causes a leftward shift, a rightward shift, or no shift in the direction of the net reaction.

leftward shift -increase the volume rightward shift -decrease the volume no shift -add more X -remove some X

For the following systems at equilibrium A: CaCO3(s) ⇌ CaO(s) + CO2(g)g ΔH = +178 kJ/mol B : PCl3(g) + Cl2(g) ⇌ PCl5(g) ΔH = -88 kJ/mol classify these changes by their effect.

leftward shift -system C decrease temperature -system D increase temperature no shift N/A rightward shift -system C increase temperature -system D decrease temperature

LiOH

lithium hydroxide (strong base)

higher OH- value

low pOH value means

When converting between Kc and Kp, this relationship will depend on the change in:

moles of gas between reactants and products

If a catalyst is added to a reaction, the reaction will most often generate products:

more rapidly

If an equilibrium reaction is exothermic in the forward direction, the change in enthalpy of the reaction will have a _______ sign, and the heat produced in the forward reaction can be listed as a _________.

negative, product

If an equilibrium reaction is exothermic in the forward direction, the change in enthalpy of the reaction will have a _______ sign, and the heat produced in the forward reaction can be listed as a _________.

negative, product Exothermic reactions have a negative change in enthalpy, and they release heat, which means heat could be considered a product in the forward reaction.

HNO3 (aq)

nitric acid (strong acid)

For the following equilibrium, what will occur if the vessel contracts: H2(g)+I2(g)⇌2HI(g)

no change

For the following equilibrium, what will occur if the vessel contracts:H2(g)+I2(g)⇌2HI(g)

no change

For the following equilibrium, what will occur if the vessel expands: H2(g)+Cl2(g)→2HCl(g)

no change

For the following equilibrium, what will occur if the vessel expands:H2(g)+Cl2(g)→2HCl(g)

no change

Consider the reaction described by the following equation. CO2(g)+H2(g)⇌CO(g)+H2O(g) How will the position of the equilibrium change if the volume of a vessel that contains this reaction is decreased?

no change will be observed

Consider the reaction described by the following equation.CO2(g)+H2(g)⇌CO(g)+H2O(g)How will the position of the equilibrium change if the volume of a vessel that contains this reaction is decreased?

no change will be observed

H3PO4 CN−

not amphiprotic

Roughly how many water molecules are ionized at any given time in a sample of room-temperature water?

one in a billion

Substances on opposite sides of the equilibrium will have relative changes in concentration that are of:

opposite sign

The hydronium ion concentration of vinegar is approximately 4.0×10−3 M. What are the corresponding values of pOH and pH?

pH = 2.40, pOH = 11.60

What is the pOH of a solution at 25.0∘C with [H3O+]=6.6×10−10 M?

pH=4.82

A solution has a pOH of 6.50 at 50∘C. What is the pH of the solution given that Kw=6.22×10−15 at this temperature? The equation relating pH and pOH at any temperature is pKw=pH+pOH Where pKw=−logKw. It is given that Kw=6.22×10−15 at 50∘C. Therefore, we can solve for the pH as follows: pH=pKw−pOH =−log(6.22×10−15)−6.50 =14.206−6.50=7.71

pH=7.71

Identify the option below that is a characteristic of acidic solutions.

pOH levels greater than 7 at 25∘C

If products are removed from a system at equilibrium, the equilibrium will: shift right shift left no change depends on the equilibrium

shift right If products are removed, the equilibrium will shift right to try to regenerate some of the products and regain equilibrium.

NaOH

sodium hydroxide (strong base)

Homogeneous equilibria will typically not exist in the:

solid phase

Kc expressions will exclude:

solids

Kc expressions will exclude: -gases -aqueous substances -solids none of the above

solids

Catalysts are primarily used in a reaction to _______.

speed up the reaction

The relative changes in concentration of the substances involved in an equilibrium as the system equilibrates can be determined by looking at the:

stoichiometry of the equilibrium

autoionization

substance ionizes when one molecule of the substance reacts with another molecule of the same substance, is referred to

H2SO4 (aq)

sulfuric acid (strong acid)

The Kc for a system will vary depending on the:

temperature of the system

dentify the options below that are results of decreasing the temperature of a system that includes an exothermic reaction in the forward direction. Select all that apply: The concentrations of the reactants increase. The concentrations of the products increase. The equilibrium shifts toward the products. The equilibrium constant decreases.

the concentrations of the products increase the equilibrium shifts toward the products

What affects the solubility of C5H11OH in water?

the hydroxyl group and the alkyl groups

Which of the following is true about the rate expressions in a chemical reaction?

the rate expression for any product will be positive, and that for any reactant will be negative Reactants are used up during a reaction, so the change in their concentrations as time moves forward is negative, giving a negative rate expression. Conversely, products are produced during a reaction, so the change in their concentrations as time moves forward is positive, giving a positive rate expression.

In the industrial production of ammonia, which of the following is affected by the catalyst? Select all that apply.

the rate of production the practical yield that can be obtained in limited time The catalyst used in the production of ammonia helps equilibrium to be reached more quickly, increasing the yield and rate of production. Catalysts do not affect equilibrium constants or concentrations.

If a stress causes the value of Q to increase, what will happen to the system?

the rate of the reverse reaction will increase

If a stress causes the value of Q to increase, what will happen to the system? the rate of the forward reaction will increase the rate of the reverse reaction will increase the system will expand the system will contract

the rate of the reverse reaction will increase

If a hot and cold object come into contact, heat is transferred until:

thermal equilibrium is reached

Which of the following will NOT result in a change in equilibrium in a reaction involving gases?

tripling the amount of all of the components in the system

Roughly how many water molecules are ionized at any given time in a sample of room-temperature water?

two in a billion

In a chemical equation, the symbol between the reactants and the products that is used to indicate an equilibrium reaction is _____________.

two stacked arrows: one pointing to the left and one to the right. reactants⇌products

A catalyst has no effect on: (select all that apply)

value of an equilibrium constant equilibrium concentrations

It can be difficult to differentiate a system at equilibrium from a system containing a

very slow chemical reaction

It can be difficult to differentiate a system at equilibrium from a system containing a:

very slow chemical reaction

How do you know when the equivalent point is reached

view w/ ph meter or an indicator

When is the average rate of a reaction equal to its instantaneous rate at a given second?

when the reaction proceeds at a constant rate

Complete the set of algebraic terms representing the changes in concentrations for the following reaction: 2NO+O2 ⇌ 2NO2

x, 12x, −x