Question 1

Write the mass-action expression, Qc, for the following chemical reaction.

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 2

What is the mass-action expression, Qp, for the following reaction?

Accepted Answer

A)    
B)    
C)    
D)    
E)  None of these choices is the correct mass-action expression. 
A)    
B)    
C)    
D)    
E)  None of these choices is the correct mass-action expression.

Question 3

A good catalyst for a reaction will speed up the forward reaction and slow down the reverse reaction.

Accepted Answer

A) True 
 B)False

Question 4

The reaction system   is at equilibrium. Which of the following statements describes the behavior of the system if the partial pressure of chlorine is reduced by 50%?

Accepted Answer

A)  POCl3 will be consumed as equilibrium is established. 
B)  POCl will be consumed as equilibrium is established. 
C)  Chlorine will be consumed as equilibrium is established. 
D)  The partial pressure of POCl will decrease while the partial pressure of Cl2 increases as equilibrium is established. 
E)  The volume will have to decrease before equilibrium can be reestablished. 
A)  POCl3 will be consumed as equilibrium is established. 
B)  POCl will be consumed as equilibrium is established. 
C)  Chlorine will be consumed as equilibrium is established. 
D)  The partial pressure of POCl will decrease while the partial pressure of Cl2 increases as equilibrium is established. 
E)  The volume will have to decrease before equilibrium can be reestablished.

Question 5

What is the mass-action expression, Qc, for the following chemical reaction?

Accepted Answer

A)    
B)    
C)    
D)    
E)  None of these choices is correct. 
A)    
B)    
C)    
D)    
E)  None of these choices is correct.

Question 6

A chemical reaction has an equilibrium constant of 2 *106. If this reaction is at equilibrium, select the one correct conclusion that can be made about the reaction.

Accepted Answer

A)  The forward and back reactions have stopped. 
B)  The limiting reactant has been used up. 
C)  The forward and reverse rate constants are equal. 
D)  The forward and reverse reaction rates are equal. 
E)  None of these choices is correct. 
A)  The forward and back reactions have stopped. 
B)  The limiting reactant has been used up. 
C)  The forward and reverse rate constants are equal. 
D)  The forward and reverse reaction rates are equal. 
E)  None of these choices is correct.

Question 7

Ammonia is synthesized in the Haber process:

Accepted Answer

K_p for this reaction

Question 8

The reaction quotient, Qc, for a reaction has a value of 75 while the equilibrium constant, Kc, has a value of 195. Which of the following statements is accurate?

Accepted Answer

A)  The reaction must proceed to the left to establish equilibrium. 
B)  The reaction must proceed to the right to establish equilibrium. 
C)  The concentrations of the products will be much smaller than the concentrations of the reactants when the system is at equilibrium. 
D)  The concentrations of the products will be about the same as the concentrations of the reactants when the system is at equilibrium. 
E)  None of these choices is correct. 
A)  The reaction must proceed to the left to establish equilibrium. 
B)  The reaction must proceed to the right to establish equilibrium. 
C)  The concentrations of the products will be much smaller than the concentrations of the reactants when the system is at equilibrium. 
D)  The concentrations of the products will be about the same as the concentrations of the reactants when the system is at equilibrium. 
E)  None of these choices is correct.

Question 9

The equilibrium constant Kc for the reaction A(g) + B(g)   C(g) is 0.76 at 150 $\degree$C. If 0.800 mol of A is added to 0.600 mol of B in a 1.00-L container at 150 $\degree$C, what will be the equilibrium concentration of C?

Accepted Answer

A)  0.19 M 
B)  0.29 M 
C)  0.36 M 
D)  0.41 M 
E)  0.51 M 
A)  0.19 M 
B)  0.29 M 
C)  0.36 M 
D)  0.41 M 
E)  0.51 M

Question 10

The reaction quotient for a gas phase reaction has a value of 2000. If the number of moles of reactants in the reaction equation is equal to that of the products, which of the following statements is definitely true?

Accepted Answer

A)  The reaction must proceed to the left to establish equilibrium. 
B)  The reaction must proceed to the right to establish equilibrium. 
C)  When the system is at equilibrium, the concentrations of the products will be much larger than the concentrations of the reactants. 
D)  The concentrations of the products are generally larger than the concentrations of the reactants. 
E)  None of these choices is correct. 
A)  The reaction must proceed to the left to establish equilibrium. 
B)  The reaction must proceed to the right to establish equilibrium. 
C)  When the system is at equilibrium, the concentrations of the products will be much larger than the concentrations of the reactants. 
D)  The concentrations of the products are generally larger than the concentrations of the reactants. 
E)  None of these choices is correct.

Question 11

The reaction system   is at equilibrium. Which of the following statements describes the behavior of the system if the partial pressure of hydrogen is doubled?

Accepted Answer

A)  As equilibrium is reestablished, the partial pressure of carbon disulfide increases. 
B)  As equilibrium is reestablished, the partial pressure of methane, CH4, decreases. 
C)  As equilibrium is reestablished, the partial pressure of hydrogen decreases. 
D)  As equilibrium is reestablished, the partial pressure of hydrogen sulfide decreases. 
E)  As equilibrium is reestablished, all the partial pressures will decrease. 
A)  As equilibrium is reestablished, the partial pressure of carbon disulfide increases. 
B)  As equilibrium is reestablished, the partial pressure of methane, CH4, decreases. 
C)  As equilibrium is reestablished, the partial pressure of hydrogen decreases. 
D)  As equilibrium is reestablished, the partial pressure of hydrogen sulfide decreases. 
E)  As equilibrium is reestablished, all the partial pressures will decrease.

Question 12

Hydrogen iodide, HI, is formed in an equilibrium reaction when gaseous hydrogen and iodine gas are heated together. If 20.0 g of hydrogen and 20.0 g of iodine are heated, forming 10.0 g of hydrogen iodide, what mass of hydrogen remains unreacted?

Accepted Answer

A)  10.0 g hydrogen remains 
B)  10.9 g hydrogen remains 
C)  15.0 g hydrogen remains 
D)  19.9 g hydrogen remains 
E)  Need to know the equilibrium constant in order to calculate the answer. 
A)  10.0 g hydrogen remains 
B)  10.9 g hydrogen remains 
C)  15.0 g hydrogen remains 
D)  19.9 g hydrogen remains 
E)  Need to know the equilibrium constant in order to calculate the answer.

Question 13

At 450 $\degree$C, tert-butyl alcohol decomposes into water and isobutene.   A reaction vessel contains these compounds at equilibrium. What will happen if the volume of the container is reduced by 50% at constant temperature?

Accepted Answer

A)  The forward reaction will proceed to reestablish equilibrium. 
B)  The reverse reaction will proceed to reestablish equilibrium. 
C)  No change occurs. 
D)  The equilibrium constant will increase. 
E)  The equilibrium constant will decrease. 
A)  The forward reaction will proceed to reestablish equilibrium. 
B)  The reverse reaction will proceed to reestablish equilibrium. 
C)  No change occurs. 
D)  The equilibrium constant will increase. 
E)  The equilibrium constant will decrease.

Question 14

Consider the following two equilibria and their respective equilibrium constants:   Which one of the following is the correct relationship between the equilibrium constants K1 and K2?

Accepted Answer

A)  K2 = 2/K1 
B)  K2 = (1/K1)2 
C)  K2 = -K1/2 
D)  K2 = 1/(2K1) 
E)  K2 = 1/(2K1)2 
A)  K2 = 2/K1 
B)  K2 = (1/K1)2 
C)  K2 = -K1/2 
D)  K2 = 1/(2K1) 
E)  K2 = 1/(2K1)2

Question 15

At 850 $\degree$C, the equilibrium constant Kp for the reaction C(s) + CO2(g)   2CO(g) has a value of 10.7. If the total pressure in the system at equilibrium is 1.000 atm, what is the partial pressure of carbon monoxide?

Accepted Answer

A)  0.362 atm 
B)  0.489 atm 
C)  0.667 atm 
D)  0.915 atm 
E)  0.921 atm 
A)  0.362 atm 
B)  0.489 atm 
C)  0.667 atm 
D)  0.915 atm 
E)  0.921 atm

Question 16

Nitric oxide and bromine were allowed to react in a sealed container. When equilibrium was reached PNO = 0.526 atm,   = 1.59 atm, and PNOBr = 7.68 atm. Calculate Kp for the reaction.

Accepted Answer

A)  7.45 * 10¯3 
B)  0.109 
C)  9.18 
D)  91.8 
E)  134 
A)  7.45 * 10¯3 
B)  0.109 
C)  9.18 
D)  91.8 
E)  134

Question 17

For a gas-phase equilibrium, a change in the pressure of any single reactant or product will change Kp.

Accepted Answer

A) True 
 B)False

Question 18

Select the mass-action expression, Qc, for the following chemical reaction equation.

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 19

Stearic acid, nature's most common fatty acid, dimerizes when dissolved in hexane:   The equilibrium constant for this reaction at 28 $\degree$C is 2900. Estimate the equilibrium constant at 38 $\degree$C.

Accepted Answer

A)  4.7 * 105 
B)  2.6 * 104 
C)  1.9 * 103 
D)  3.2 * 102 
E)  18 
A)  4.7 * 105 
B)  2.6 * 104 
C)  1.9 * 103 
D)  3.2 * 102 
E)  18

Question 20

The equilibrium constant Kc for the reaction   is 49 at 230 $\degree$C. If 0.70 mol of PCl3 is added to 0.70 mol of Cl2 in a 1.00-L reaction vessel at 230 $\degree$C, what is the concentration of PCl3 when equilibrium has been established?

Accepted Answer

A)  0.049 M 
B)  0.11 M 
C)  0.30 M 
D)  0.59 M 
E)  0.83 M 
A)  0.049 M 
B)  0.11 M 
C)  0.30 M 
D)  0.59 M 
E)  0.83 M

Write the mass-action expression, Q_c, for the following chemical reaction.

What is the mass-action expression, Q_p, for the following reaction?

A good catalyst for a reaction will speed up the forward reaction and slow down the reverse reaction.

The reaction system is at equilibrium. Which of the following statements describes the behavior of the system if the partial pressure of chlorine is reduced by 50%?

What is the mass-action expression, Q_c, for the following chemical reaction?

A chemical reaction has an equilibrium constant of 2 *10⁶. If this reaction is at equilibrium, select the one correct conclusion that can be made about the reaction.

Ammonia is synthesized in the Haber process:

The reaction quotient, Q_c, for a reaction has a value of 75 while the equilibrium constant, K_c, has a value of 195. Which of the following statements is accurate?

The reaction quotient for a gas phase reaction has a value of 2000. If the number of moles of reactants in the reaction equation is equal to that of the products, which of the following statements is definitely true?

The reaction system is at equilibrium. Which of the following statements describes the behavior of the system if the partial pressure of hydrogen is doubled?

Hydrogen iodide, HI, is formed in an equilibrium reaction when gaseous hydrogen and iodine gas are heated together. If 20.0 g of hydrogen and 20.0 g of iodine are heated, forming 10.0 g of hydrogen iodide, what mass of hydrogen remains unreacted?

Consider the following two equilibria and their respective equilibrium constants: Which one of the following is the correct relationship between the equilibrium constants K₁ and K₂?

Nitric oxide and bromine were allowed to react in a sealed container. When equilibrium was reached P_NO = 0.526 atm, = 1.59 atm, and P_NOBr = 7.68 atm. Calculate K_p for the reaction.

For a gas-phase equilibrium, a change in the pressure of any single reactant or product will change K_p.

Select the mass-action expression, Q_c, for the following chemical reaction equation.

Keys to the Study of Chemistry

The Components of Matter

Stoichiometry of Formulas and Equations

Three Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry: Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces: Liquids, Solids, and Phase Changes

The Properties of Mixtures: Solutions and Colloids

Periodic Patterns in the Main-Group Elements

Organic Compounds and the Atomic Properties of Carbon

Kinetics: Rates and Mechanisms of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions

Electrochemistry: Chemical Change and Electrical Work

The Elements in Nature and Industry

The Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

Exam 17: Equilibrium: the Extent of Chemical Reactions

Write the mass-action expression, Qc, for the following chemical reaction.

What is the mass-action expression, Qp, for the following reaction?

A good catalyst for a reaction will speed up the forward reaction and slow down the reverse reaction.

The reaction system is at equilibrium. Which of the following statements describes the behavior of the system if the partial pressure of chlorine is reduced by 50%?

What is the mass-action expression, Qc, for the following chemical reaction?

A chemical reaction has an equilibrium constant of 2 *106. If this reaction is at equilibrium, select the one correct conclusion that can be made about the reaction.

Ammonia is synthesized in the Haber process:

The reaction quotient, Qc, for a reaction has a value of 75 while the equilibrium constant, Kc, has a value of 195. Which of the following statements is accurate?

The equilibrium constant Kc for the reaction A(g) + B(g) C(g) is 0.76 at 150 °\degree° C. If 0.800 mol of A is added to 0.600 mol of B in a 1.00-L container at 150 °\degree° C, what will be the equilibrium concentration of C?

The reaction quotient for a gas phase reaction has a value of 2000. If the number of moles of reactants in the reaction equation is equal to that of the products, which of the following statements is definitely true?

The reaction system is at equilibrium. Which of the following statements describes the behavior of the system if the partial pressure of hydrogen is doubled?

Hydrogen iodide, HI, is formed in an equilibrium reaction when gaseous hydrogen and iodine gas are heated together. If 20.0 g of hydrogen and 20.0 g of iodine are heated, forming 10.0 g of hydrogen iodide, what mass of hydrogen remains unreacted?

At 450 °\degree° C, tert-butyl alcohol decomposes into water and isobutene. A reaction vessel contains these compounds at equilibrium. What will happen if the volume of the container is reduced by 50% at constant temperature?

Consider the following two equilibria and their respective equilibrium constants: Which one of the following is the correct relationship between the equilibrium constants K1 and K2?

At 850 °\degree° C, the equilibrium constant Kp for the reaction C(s) + CO2(g) 2CO(g) has a value of 10.7. If the total pressure in the system at equilibrium is 1.000 atm, what is the partial pressure of carbon monoxide?

Nitric oxide and bromine were allowed to react in a sealed container. When equilibrium was reached PNO = 0.526 atm, = 1.59 atm, and PNOBr = 7.68 atm. Calculate Kp for the reaction.

For a gas-phase equilibrium, a change in the pressure of any single reactant or product will change Kp.

Select the mass-action expression, Qc, for the following chemical reaction equation.

Stearic acid, nature's most common fatty acid, dimerizes when dissolved in hexane: The equilibrium constant for this reaction at 28 °\degree° C is 2900. Estimate the equilibrium constant at 38 °\degree° C.

The equilibrium constant Kc for the reaction is 49 at 230 °\degree° C. If 0.70 mol of PCl3 is added to 0.70 mol of Cl2 in a 1.00-L reaction vessel at 230 °\degree° C, what is the concentration of PCl3 when equilibrium has been established?

Keys to the Study of Chemistry

The Components of Matter

Stoichiometry of Formulas and Equations

Three Major Classes of Chemical Reactions

Gases and the Kinetic-Molecular Theory

Thermochemistry: Energy Flow and Chemical Change

Quantum Theory and Atomic Structure

Electron Configuration and Chemical Periodicity

Models of Chemical Bonding

The Shapes of Molecules

Theories of Covalent Bonding

Intermolecular Forces: Liquids, Solids, and Phase Changes

The Properties of Mixtures: Solutions and Colloids

Periodic Patterns in the Main-Group Elements

Organic Compounds and the Atomic Properties of Carbon

Kinetics: Rates and Mechanisms of Chemical Reactions

Acid-Base Equilibria

Ionic Equilibria in Aqueous Systems

Thermodynamics: Entropy, Free Energy, and the Direction of Chemical Reactions

Electrochemistry: Chemical Change and Electrical Work

The Elements in Nature and Industry

The Transition Elements and Their Coordination Compounds

Nuclear Reactions and Their Applications

Filters

Write the mass-action expression, Q_c, for the following chemical reaction.

What is the mass-action expression, Q_p, for the following reaction?

What is the mass-action expression, Q_c, for the following chemical reaction?

A chemical reaction has an equilibrium constant of 2 *10⁶. If this reaction is at equilibrium, select the one correct conclusion that can be made about the reaction.

The reaction quotient, Q_c, for a reaction has a value of 75 while the equilibrium constant, K_c, has a value of 195. Which of the following statements is accurate?

Consider the following two equilibria and their respective equilibrium constants: Which one of the following is the correct relationship between the equilibrium constants K₁ and K₂?

Nitric oxide and bromine were allowed to react in a sealed container. When equilibrium was reached P_NO = 0.526 atm, = 1.59 atm, and P_NOBr = 7.68 atm. Calculate K_p for the reaction.

For a gas-phase equilibrium, a change in the pressure of any single reactant or product will change K_p.

Select the mass-action expression, Q_c, for the following chemical reaction equation.