Ch 17 Practice

1.

1 point

NaOH (s) <--> Na+ (aq) + OH- (aq) + energy

How does the equilibrium shift when temperature is decreased?

Shifts left

Shifts right

No change

2.

1 point

N2 (g) + 3 H2 (g) <--> 2 NH3 (g) + energy

How does the equilibrium shift when N2 is added?

Shifts left

Shifts right

No change

3.

1 point

NaOH (s) <--> Na+ (aq) + OH- (aq) + energy

How does the equilibrium shift when OH- is removed?

Shifts left

Shifts right

No change

4.

1 point

What is the equilibrium expression for
Mg(OH)2 (s) + CO3 2- (aq) <--> MgCO3 (s) + 2 OH- (aq)

[OH-] / [CO3 2-]

[OH-][MgCO3] / [Mg(OH)2][CO3 2-]

[MgCO3][OH-]^2 / [CO3 2-][Mg(OH)2]

[OH-]^2 / [CO3 2-]

5.

1 point

Which of the following is FALSE about catalysts?

Raises the activation energy.

Speeds up the reaction.

Not consumed in the reaction.

Increases the rate of the reaction.

Enzymes put molecules in the right orientation for the reaction.

6.

1 point

What is the correct equilibrium expression for CO2 (aq) + H2O (l) <--> H+ (aq) + HCO3- (aq)?

1

[H+][HCO3-] / [CO2]

[H+][HCO3-] / [CO2][H2O]

1/[H2O]

7.

1 point

N2 (g) + 3 H2 (g) <--> 2 NH3 (g) + energy

What happens to the concentration of NH3 when temperature is increased?

Decreases

Increases

No change

8.

1 point

N2 (g) + 3 H2 (g) <--> 2 NH3 (g) + energy

How does the equilibrium shift when H2 is removed?

Shifts left

Shifts right

No change

9.

1 point

What is the correct equilibrium expression for 2 HBr (g) <--> H2 (g) + Br2 (l)?

[Br2][H2] / [HBr]^2

[HBr]^2 / [Br2][H2]

[H2] / [HBr]^2

[HBr]^2 / [H2]

10.

1 point

Calculate the equilibrium constant for PCl5 (g) <--> PCl3 (g) + Cl2 (g) if the equilibrium concentration of PCl5 is 0.0096M, PCl3 is 0.0247M, and Cl2 is 0.0247M.

0.064

16

0.06355

15.7

11.

1 point

NaOH (s) <--> Na+ (aq) + OH- (aq) + energy

How does the equilibrium shift when Na+ is added?

Shifts left

Shifts right

No change

12.

1 point

Is this at equilibrium? For the reaction 2 CO (g) <--> C (s) + CO2 (g) with K = 7.7x10^-15, the concentration of [CO] = 0.034M and [CO2] = 3.6x10^-17M.

Yes

No

13.

1 point

N2 (g) + 3 H2 (g) <--> 2 NH3 (g) + energy

How does the equilibrium shift when pressure is increased?

Shifts left

Shifts right

No change

14.

1 point

N2 (g) + 3 H2 (g) <--> 2 NH3 (g) + energy

What happens to the concentration of H2 when more N2 is added to the system?

Decreases

Increases

No change

15.

1 point

(Choose all that apply)

What is true about equilibrium?

Equilibrium constant K represents the ratio of products to reactants.

Happens only at one specific set of concentrations of reactants and products.

Equilibrium constant K represents how fast the reaction is going.

Rate of the forward and the reverse reactions are the same.

Concentration of the product remains the same over time.

Reactants and products have the same concentration.

Gases, liquids, and aqueous substances are included in the equilibrium expression.

Equilibrium constant K is calculated from initial concentrations of substances.