Chemistry

Kinetics and Equilibrium 1

1. Matching:

A. inhibitor the rate at which reactant disappears or product appears

B. catalyst a substance that decreases reaction rate

C. reaction rate a substance that lowers activation energy

D. activation energy highest energy species in a reaction pathway

E. activated complex energy required to start a reaction

2. Tell whether each decreases or increases reaction rates:

A. increasing pressure

B. decreasing concentration

C. adding a catalyst

D. adding an inhibitor

E. increasing temperature

F. decreasing temperature

G. agitation

3. Given the mechanism find: catalyst, intermediate(s), reactants and products

A + B = C

C + A = D + B

4. A reaction follows the rate law rate = k[A][B]2 What happens to the rate when we

A. double [A] B. triple [B] C. double [A] and [B] D. double [A] and halve [B]

5. Equilibrium is when:

6. Write equilibrium expressions for:

A. H2(g) + 1/2O2(g) = H2O(g)

B. 2H2(g) + O2(g) = 2H2O(g)

C. 2H2(g) + O2(g) = 2H2O(l)

3H2(g) = N2(g) = 2NH3(g)

NH3(g) = 1/2N2(g) + 3/2H2(g)

P4(s) = 5O2(g) = P4O10(s)

7. At a given temperature, the reaction (all gases) CO + H2O H2 + CO2 produces the following concentrations: CO = 0.200M; H2O = 0.500M; H2 = 0.32M; CO2 = 0.42M. Find the Keq at that temperature.

8. What is the equilibrium constant for the following reaction if the final concentrations are CH3COOH = 0.302 M, CH3CH2OH = 0.428 M, H2O = 0.654 M, and CH3CH2OOCCH3 = 0.655 M?

CH3COOH + CH3CH2OH CH3CH2OOCCH3 + H2O

9. What is the equilibrium concentration of SO3 in the following reaction if the concentration of SO2 and O2 are each 0.0500M and Keq = 85.0? The equation for the reaction is

2 SO2 + O2 2 SO3

10. If the temperature in the reaction in #2 is changed, the Keq becomes 2.40. By removing some H2 and CO2 and adding H2O all concentrations except CO are adjusted to the values given in # 2. What is the new CO concentration?

11. At 60.2°C, the equilibrium constant (Keq) for the reaction, N2O4(g) 2 NO2(g), is

8.75 x 10-2. At this temperature, a vessel contains nitrogen tetroxide, N2O4, at a concentration of 1.72 x 10-2 M at equilibrium. What concentration of nitrogen dioxide, NO2, does it contain?

12. Determine the equilibrium constant of the following chemical reaction using the data given.

2 SO2 + O2 2 SO3

At equilibrium at 295°C, a 2.00-L flask was found to contain 0.35 moles of SO2, 0.70 moles of O2, and 1.40 moles SO3.

13. At 2000°C, nitrogen and oxygen react according to the following equation.

N2 + O2 2 NO

The equilibrium constant for this reaction at 2000°C is 1.2 x 10-4. At equilibrium, the concentrations of N2 and O2 are found to be 0.166 M and 0.145 M respectively. What is the concentration of NO?

14. If Keq for 2A + B 2C is 8.0 set up the expression used to calculate the concentration of C at equilibrium. Calculate the equilibrium concentration of C if the starting conditions were 0.50 mol each of A and B in a 10.0-L container.

15. Ammonia combines with oxygen to produce water vapor and nitrogen.

a.  Write a balanced equation for the equilibrium reaction.

b.  Write the expression for the equilibrium constant.

c.  At a certain temperature, the concentration of each substance is 1.0 M. Calculate Keq for that temperature.

d.  Calculate Keq if NH3 is 3.0 M, O2 is 2.0 M, H2O is 4.0 M, and N2 is 2.0 M

16. In the last section, study the discussion of the equilibrium established in the Haber process. N2(g) + 3H2(g) 2NH3(g) + energy

a. Explain the effect of increasing the concentration of reactants.

b. Explain the effect of increasing the pressure on the system.

c. Explain the effect of increasing the temperature of the system.

d. What would be the effect of removing the ammonia formed during the reaction?