Question 1

Which statement about the equilibrium constant is true? The value of Kc

Accepted Answer

A) changes as product concentration changes. 
B) changes as reactant concentration changes. 
C) changes as temperature changes. 
D) never changes. 
A) changes as product concentration changes. 
B) changes as reactant concentration changes. 
C) changes as temperature changes. 
D) never changes.

Question 2

Shown below is a concentration vs.time plot for the reaction A ⇌ 2B.For this reaction the value of the equilibrium constant is

Accepted Answer

A) Kc c = 0. 
C) Kc = 1. 
D) Kc > 1. 
A) Kc c = 0. 
C) Kc = 1. 
D) Kc > 1.

Question 3

A catalyst increases the rate of a chemical reaction by providing a lower-energy mechanism for the reaction.When this occurs,which one of the following is not affected?

Accepted Answer

A) activation energy for the forward reaction 
B) activation energy for the reverse reaction 
C) equilibrium constant 
D) rate of the reverse reaction 
A) activation energy for the forward reaction 
B) activation energy for the reverse reaction 
C) equilibrium constant 
D) rate of the reverse reaction

Question 4

Picture (1)represents the equilibrium mixture for the reaction A + B ⇌ 2 AB at 298 K.  
-If this reaction is endothermic,which picture (2)-(4)represents the equilibrium mixture at 400 K?

Accepted Answer

A) picture (2) 
B) picture (3) 
C) picture (4) 
D) None of these 
A) picture (2) 
B) picture (3) 
C) picture (4) 
D) None of these

Question 5

Picture (1)represents an equilibrium mixture of solid CaCOS1U1B13S1U1B0,solid CaO,and gaseous COS1U1B12S1U1B0,obtained as a result of the endothermic decomposition of CaCOS1U1B13S1U1B0.  
-Which picture (2)-(4)represents the equilibrium mixture at a higher temperature?

Accepted Answer

A) picture (2) 
B) picture (3) 
C) picture (4) 
D) None of these 
A) picture (2) 
B) picture (3) 
C) picture (4) 
D) None of these

Question 6

For acid solutions of the same molarity acid strength is proportional to the equilibrium concentration of H3O+.For equimolar solutions of acids,which equilibrium expression below corresponds to the strongest acid?

Accepted Answer

A) Kc =   = 3.5 × 10-4 
B) Kc =   = 3.5 × 10-8 
C) Kc =   = 4.5 × 10-4 
D) Kc =   = 4.9 × 10-10 
A) Kc =   = 3.5 × 10-4 
B) Kc =   = 3.5 × 10-8 
C) Kc =   = 4.5 × 10-4 
D) Kc =   = 4.9 × 10-10

Question 7

Find the equilibrium constant for the reaction: A(g)+ B(g)⇌ 2C(g)at 25°C when k equals 1.4 × 10-12 M-1s-1 for the reaction A(g)+ B(g)⇌ 2C(g)at 25°C and k equals 2.7 × 10-13 M-1s-1 for the reaction: 2 C(g)⇌ A(g)+ B(g)at 25°C.

Accepted Answer

A) 3)8 × 10-25 
B) 1)7 × 10-12 
C) 1)1 × 10-12 
D) 5)2 
A) 3)8 × 10-25 
B) 1)7 × 10-12 
C) 1)1 × 10-12 
D) 5)2

Question 8

For the reaction 2 A + B2 ⇌ 2 AB,the rate of the forward reaction is 0.75 M/s and the rate of the reverse reaction is 0.25 M/s.The reaction is not at equilibrium.In order to attain equilibrium the reaction must proceed in the ________ (forward,reverse)direction in order to achieve equilibrium.

Accepted Answer

Question 9

The solubility of 1:1 salts is measured by the equilibrium constant for the general reaction: MX(s)= Mn+(aq)+ Xn-(aq).Given the following salts and their equilibrium constants for the reaction above at 25°C,which salt is the least soluble?

Accepted Answer

A) MgCO3,Kc = 6.8 × 10-6 
B) CaCO3,Kc = 5.0 × 10-9 
C) SrCO3,Kc = 5.6 × 10-10 
D) BaCO3,Kc = 2.6 × 10-9 
A) MgCO3,Kc = 6.8 × 10-6 
B) CaCO3,Kc = 5.0 × 10-9 
C) SrCO3,Kc = 5.6 × 10-10 
D) BaCO3,Kc = 2.6 × 10-9

Question 10

Shown below is a concentration vs.time plot for the reaction A ⇌ B.For this reaction the value of the equilibrium constant is

Accepted Answer

A) Kc c = 0. 
C) Kc = 1. 
D) Kc > 1. 
A) Kc c = 0. 
C) Kc = 1. 
D) Kc > 1.

Question 11

According to Le Châtelier's principle,if the volume of the vessel containing the equilibrium system shown below is decreased,there will be an increase in the concentration of ________ and a decrease in the concentration of ________.
H2(g)⇌ 2 H(g)

Accepted Answer

Question 12

The decomposition of nitrosyl bromide is exothermic: 2 NOBr(g)⇌ 2 NO(g)+ Br2(g).Which of the following changes in reaction condition will shift the reaction to the left?

Accepted Answer

A) add more NOBr 
B) decrease the temperature 
C) increase the container volume 
D) None of these 
A) add more NOBr 
B) decrease the temperature 
C) increase the container volume 
D) None of these

Question 13

The overall reaction for photosynthesis can be represented by the following equation:
6 CO2(g)+ 6 H2O(l)⇌ C6H12O6(s)+ 6 O2(g)
The enthalpy change for this reaction is 2802 kJ.Which of the following changes in condition will shift the equilibrium to the right?

Accepted Answer

A) increase the pressure of O2 
B) increase the temperature 
C) remove CO2 by reaction with CaO(s) 
D) remove one-half of C6H12O6(s) 
A) increase the pressure of O2 
B) increase the temperature 
C) remove CO2 by reaction with CaO(s) 
D) remove one-half of C6H12O6(s)

Question 14

Given the reaction at a certain temperature: 2 HI(g)⇌ H2(g)+ I2(g).At equilibrium,the partial pressure of HI is 1.8 × 10-3 atm,and the partial pressures for H2 and I2 are 0.10 atm each.Find Kp at that temperature.

Accepted Answer

A) 3)2 × 10-4 
B) 5)6 × 101 
C) 3)1 × 103 
D) 3)1 × 104 
A) 3)2 × 10-4 
B) 5)6 × 101 
C) 3)1 × 103 
D) 3)1 × 104

Question 15

Cyclohexane,C6H12,undergoes a molecular rearrangement in the presence of AlCl3 to form methylcyclopentane,CH3C5H9, according to the equation:
C6H12 ⇌ CH3C5H9
If Kc = 0.143 at 25°C for this reaction,find the equilibrium concentrations of C6H12 and CH3C5H9 if the initial concentrations are 0.200 M and 0.075 M,respectively.

Accepted Answer

A) [C6H12] = 0.041 M,[CH3C5H9] = 0.041 M 
B) [C6H12] = 0.159 M,[CH3C5H9] = 0.116 M 
C) [C6H12] = 0.241 M,[CH3C5H9] = 0.034 M 
D) [C6H12] = 0.253 M,[CH3C5H9] = 0.022 M 
A) [C6H12] = 0.041 M,[CH3C5H9] = 0.041 M 
B) [C6H12] = 0.159 M,[CH3C5H9] = 0.116 M 
C) [C6H12] = 0.241 M,[CH3C5H9] = 0.034 M 
D) [C6H12] = 0.253 M,[CH3C5H9] = 0.022 M

Question 16

For the reaction A2 + 2 B3 ⇌ 2 AB3,the rate of the forward reaction is 0.25 M/s and the rate of the reverse reaction is 0.75 M/s.The reaction is not at equilibrium.In order to attain equilibrium the reaction must proceed in the ________ (forward,reverse)direction in order to achieve equilibrium.

Accepted Answer

Question 17

Which of the following changes in reaction conditions will not alter the composition of a homogeneous equilibrium mixture of gases in a reaction having unequal moles of gaseous products and reactants?

Accepted Answer

A) addition of a catalyst 
B) addition of reactants or products 
C) decreasing the temperature 
D) increasing the pressure or volume 
A) addition of a catalyst 
B) addition of reactants or products 
C) decreasing the temperature 
D) increasing the pressure or volume

Question 18

What is the equilibrium equation for the following reaction?
C2H4 (g)+ 3 O2 (g)⇌ 2 CO2 (g)+ 2 H2O (l)

Accepted Answer

A) Kp =   
B) Kp =   
C) Kp =   
D) Kp =   
A) Kp =   
B) Kp =   
C) Kp =   
D) Kp =

Question 19

Cyclohexane (C6H12)undergoes a molecular rearrangement in the presence of AlCl3 to form methylcyclopentane (CH3C5H9)according to the equation:
C6H12 ⇌ CH3C5H9
If Kc = 0.143 at 25°C for this reaction,find the equilibrium concentrations of C6H12 and CH3C5H9 if the initial concentrations are 0.200 M and 0.100 M,respectively.

Accepted Answer

A) [C6H12] = 0.0625 and [CH3C5H9] = 0.062 M 
B) [C6H12] = 0.138 and [CH3C5H9] = 0.162 M 
C) [C6H12] = 0.262 M and [CH3C5H9] = 0.038 M 
D) [C6H12] = 0.282 and [CH3C5H9] = 0.018 M 
A) [C6H12] = 0.0625 and [CH3C5H9] = 0.062 M 
B) [C6H12] = 0.138 and [CH3C5H9] = 0.162 M 
C) [C6H12] = 0.262 M and [CH3C5H9] = 0.038 M 
D) [C6H12] = 0.282 and [CH3C5H9] = 0.018 M

Question 20

Picture (1)represents an equilibrium mixture of solid CaCOS1U1B13S1U1B0,solid CaO,and gaseous COS1U1B12S1U1B0,obtained as a result of the endothermic decomposition of CaCOS1U1B13S1U1B0.  
-Which picture (2)-(4)represents the equilibrium mixture when more solid CaCO3 is added?

Accepted Answer

A) picture (2) 
B) picture (3) 
C) picture (4) 
D) All of these 
A) picture (2) 
B) picture (3) 
C) picture (4) 
D) All of these

Which statement about the equilibrium constant is true? The value of K_c

Shown below is a concentration vs.time plot for the reaction A ⇌ 2B.For this reaction the value of the equilibrium constant is

A catalyst increases the rate of a chemical reaction by providing a lower-energy mechanism for the reaction.When this occurs,which one of the following is not affected?

Picture (1)represents the equilibrium mixture for the reaction A + B ⇌ 2 AB at 298 K. -If this reaction is endothermic,which picture (2)-(4)represents the equilibrium mixture at 400 K?

Picture (1)represents an equilibrium mixture of solid CaCO₃,solid CaO,and gaseous CO₂,obtained as a result of the endothermic decomposition of CaCO₃. -Which picture (2)-(4)represents the equilibrium mixture at a higher temperature?

For acid solutions of the same molarity acid strength is proportional to the equilibrium concentration of H₃O⁺.For equimolar solutions of acids,which equilibrium expression below corresponds to the strongest acid?

Find the equilibrium constant for the reaction: A(g)+ B(g)⇌ 2C(g)at 25°C when k equals 1.4 × 10^-12 M^-1s^-1 for the reaction A(g)+ B(g)⇌ 2C(g)at 25°C and k equals 2.7 × 10^-13 M^-1s^-1 for the reaction: 2 C(g)⇌ A(g)+ B(g)at 25°C.

For the reaction 2 A + B₂ ⇌ 2 AB,the rate of the forward reaction is 0.75 M/s and the rate of the reverse reaction is 0.25 M/s.The reaction is not at equilibrium.In order to attain equilibrium the reaction must proceed in the ________ (forward,reverse)direction in order to achieve equilibrium.

The solubility of 1:1 salts is measured by the equilibrium constant for the general reaction: MX(s)= Mⁿ⁺(aq)+ X^n-(aq).Given the following salts and their equilibrium constants for the reaction above at 25°C,which salt is the least soluble?

Shown below is a concentration vs.time plot for the reaction A ⇌ B.For this reaction the value of the equilibrium constant is

According to Le Châtelier's principle,if the volume of the vessel containing the equilibrium system shown below is decreased,there will be an increase in the concentration of and a decrease in the concentration of . H₂(g)⇌ 2 H(g)

The decomposition of nitrosyl bromide is exothermic: 2 NOBr(g)⇌ 2 NO(g)+ Br₂(g).Which of the following changes in reaction condition will shift the reaction to the left?

The overall reaction for photosynthesis can be represented by the following equation: 6 CO₂(g)+ 6 H₂O(l)⇌ C₆H₁₂O₆(s)+ 6 O₂(g) The enthalpy change for this reaction is 2802 kJ.Which of the following changes in condition will shift the equilibrium to the right?

Given the reaction at a certain temperature: 2 HI(g)⇌ H₂(g)+ I₂(g).At equilibrium,the partial pressure of HI is 1.8 × 10^-3 atm,and the partial pressures for H₂ and I₂ are 0.10 atm each.Find K_p at that temperature.

Which of the following changes in reaction conditions will not alter the composition of a homogeneous equilibrium mixture of gases in a reaction having unequal moles of gaseous products and reactants?

What is the equilibrium equation for the following reaction? C₂H₄ (g)+ 3 O₂ (g)⇌ 2 CO₂ (g)+ 2 H₂O (l)

Picture (1)represents an equilibrium mixture of solid CaCO₃,solid CaO,and gaseous CO₂,obtained as a result of the endothermic decomposition of CaCO₃. -Which picture (2)-(4)represents the equilibrium mixture when more solid CaCO₃ is added?

Chemistry: Matter and Measurement

Atoms, molecules, and Ions

Formulas, equations, and Moles

Reactions in Aqueous Solutions

Periodicity and the Atomic Structure of Atoms

Ionic Bonds and Some Main-Group Chemistry

Covalent Bonds and Molecular Structure

Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

Liquids,solids,and Phase Changes

Solutions and Their Properties

Chemical Kinetics

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Hydrogen, oxygen, and Water

The Main-Group Elements

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

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Exam 13: Chemical Equilibrium

Which statement about the equilibrium constant is true? The value of Kc

Shown below is a concentration vs.time plot for the reaction A ⇌ 2B.For this reaction the value of the equilibrium constant is

A catalyst increases the rate of a chemical reaction by providing a lower-energy mechanism for the reaction.When this occurs,which one of the following is not affected?

Picture (1)represents the equilibrium mixture for the reaction A + B ⇌ 2 AB at 298 K. -If this reaction is endothermic,which picture (2)-(4)represents the equilibrium mixture at 400 K?

Picture (1)represents an equilibrium mixture of solid CaCO3,solid CaO,and gaseous CO2,obtained as a result of the endothermic decomposition of CaCO3. -Which picture (2)-(4)represents the equilibrium mixture at a higher temperature?

For acid solutions of the same molarity acid strength is proportional to the equilibrium concentration of H3O+.For equimolar solutions of acids,which equilibrium expression below corresponds to the strongest acid?

Find the equilibrium constant for the reaction: A(g)+ B(g)⇌ 2C(g)at 25°C when k equals 1.4 × 10-12 M-1s-1 for the reaction A(g)+ B(g)⇌ 2C(g)at 25°C and k equals 2.7 × 10-13 M-1s-1 for the reaction: 2 C(g)⇌ A(g)+ B(g)at 25°C.

For the reaction 2 A + B2 ⇌ 2 AB,the rate of the forward reaction is 0.75 M/s and the rate of the reverse reaction is 0.25 M/s.The reaction is not at equilibrium.In order to attain equilibrium the reaction must proceed in the ________ (forward,reverse)direction in order to achieve equilibrium.

The solubility of 1:1 salts is measured by the equilibrium constant for the general reaction: MX(s)= Mn+(aq)+ Xn-(aq).Given the following salts and their equilibrium constants for the reaction above at 25°C,which salt is the least soluble?

Shown below is a concentration vs.time plot for the reaction A ⇌ B.For this reaction the value of the equilibrium constant is

According to Le Châtelier's principle,if the volume of the vessel containing the equilibrium system shown below is decreased,there will be an increase in the concentration of ________ and a decrease in the concentration of ________. H2(g)⇌ 2 H(g)

The decomposition of nitrosyl bromide is exothermic: 2 NOBr(g)⇌ 2 NO(g)+ Br2(g).Which of the following changes in reaction condition will shift the reaction to the left?

The overall reaction for photosynthesis can be represented by the following equation: 6 CO2(g)+ 6 H2O(l)⇌ C6H12O6(s)+ 6 O2(g) The enthalpy change for this reaction is 2802 kJ.Which of the following changes in condition will shift the equilibrium to the right?

Given the reaction at a certain temperature: 2 HI(g)⇌ H2(g)+ I2(g).At equilibrium,the partial pressure of HI is 1.8 × 10-3 atm,and the partial pressures for H2 and I2 are 0.10 atm each.Find Kp at that temperature.

For the reaction A2 + 2 B3 ⇌ 2 AB3,the rate of the forward reaction is 0.25 M/s and the rate of the reverse reaction is 0.75 M/s.The reaction is not at equilibrium.In order to attain equilibrium the reaction must proceed in the ________ (forward,reverse)direction in order to achieve equilibrium.

Which of the following changes in reaction conditions will not alter the composition of a homogeneous equilibrium mixture of gases in a reaction having unequal moles of gaseous products and reactants?

What is the equilibrium equation for the following reaction? C2H4 (g)+ 3 O2 (g)⇌ 2 CO2 (g)+ 2 H2O (l)

Picture (1)represents an equilibrium mixture of solid CaCO3,solid CaO,and gaseous CO2,obtained as a result of the endothermic decomposition of CaCO3. -Which picture (2)-(4)represents the equilibrium mixture when more solid CaCO3 is added?

Chemistry: Matter and Measurement

Atoms, molecules, and Ions

Formulas, equations, and Moles

Reactions in Aqueous Solutions

Periodicity and the Atomic Structure of Atoms

Ionic Bonds and Some Main-Group Chemistry

Covalent Bonds and Molecular Structure

Thermochemistry: Chemical Energy

Gases: Their Properties and Behavior

Liquids,solids,and Phase Changes

Solutions and Their Properties

Chemical Kinetics

Aqueous Equilibria: Acids and Bases

Applications of Aqueous Equilibria

Thermodynamics: Entropy, free Energy, and Equilibrium

Electrochemistry

Hydrogen, oxygen, and Water

The Main-Group Elements

Transition Elements and Coordination Chemistry

Metals and Solid-State Materials

Nuclear Chemistry

Organic and Biological Chemistry

Filters

Which statement about the equilibrium constant is true? The value of K_c

Picture (1)represents an equilibrium mixture of solid CaCO₃,solid CaO,and gaseous CO₂,obtained as a result of the endothermic decomposition of CaCO₃. -Which picture (2)-(4)represents the equilibrium mixture at a higher temperature?

For acid solutions of the same molarity acid strength is proportional to the equilibrium concentration of H₃O⁺.For equimolar solutions of acids,which equilibrium expression below corresponds to the strongest acid?

Find the equilibrium constant for the reaction: A(g)+ B(g)⇌ 2C(g)at 25°C when k equals 1.4 × 10^-12 M^-1s^-1 for the reaction A(g)+ B(g)⇌ 2C(g)at 25°C and k equals 2.7 × 10^-13 M^-1s^-1 for the reaction: 2 C(g)⇌ A(g)+ B(g)at 25°C.

For the reaction 2 A + B₂ ⇌ 2 AB,the rate of the forward reaction is 0.75 M/s and the rate of the reverse reaction is 0.25 M/s.The reaction is not at equilibrium.In order to attain equilibrium the reaction must proceed in the ________ (forward,reverse)direction in order to achieve equilibrium.

The solubility of 1:1 salts is measured by the equilibrium constant for the general reaction: MX(s)= Mⁿ⁺(aq)+ X^n-(aq).Given the following salts and their equilibrium constants for the reaction above at 25°C,which salt is the least soluble?

According to Le Châtelier's principle,if the volume of the vessel containing the equilibrium system shown below is decreased,there will be an increase in the concentration of and a decrease in the concentration of . H₂(g)⇌ 2 H(g)

The decomposition of nitrosyl bromide is exothermic: 2 NOBr(g)⇌ 2 NO(g)+ Br₂(g).Which of the following changes in reaction condition will shift the reaction to the left?

The overall reaction for photosynthesis can be represented by the following equation: 6 CO₂(g)+ 6 H₂O(l)⇌ C₆H₁₂O₆(s)+ 6 O₂(g) The enthalpy change for this reaction is 2802 kJ.Which of the following changes in condition will shift the equilibrium to the right?

Given the reaction at a certain temperature: 2 HI(g)⇌ H₂(g)+ I₂(g).At equilibrium,the partial pressure of HI is 1.8 × 10^-3 atm,and the partial pressures for H₂ and I₂ are 0.10 atm each.Find K_p at that temperature.

What is the equilibrium equation for the following reaction? C₂H₄ (g)+ 3 O₂ (g)⇌ 2 CO₂ (g)+ 2 H₂O (l)

Picture (1)represents an equilibrium mixture of solid CaCO₃,solid CaO,and gaseous CO₂,obtained as a result of the endothermic decomposition of CaCO₃. -Which picture (2)-(4)represents the equilibrium mixture when more solid CaCO₃ is added?