Question

Give an example of a reversible reaction and an irreversible reaction.

2. Explain how they are fundamentally different. Equilibrium is a dynamic process. Explain what this means.

3. Determine whether the following statements are true or false. Correct the false statements.

a. When a chemical reaction reaches equilibrium, the reaction completely stops.

b. When a chemical reaction reaches equilibrium, the forward reaction stops and the reverse reaction begins.

4. Determine whether the following statements are true or false. Correct the false statements.

a. The concentrations of the products are equal to the concentrations of the reactants at equilibrium.

b. The rates of the forward and reverse reactions are the same at equilibrium.

5. Consider the reversible reaction A + B ⇌ C + D.

a. If A and B are placed together in a flask and allowed to react, which species will be present at equilibrium?

b. If C and D are placed together in a flask and allowed to reaction, which species will be present at equilibrium?

6. Equilibrium Constants For the following reactions, determine whether the forward or reverse reaction is favored.

a. 2 SO3(g) ⇌ 2 SO2(g) + O2(g) K = 2.5 × 10^25

b. N2(g) + O2(g) ⇌ 2 NO(g) K = 4.1 × 10^−31

c. H2(g) + Cl2(g) ⇌ 2 HCl(g) K = 5.1 × 10^8

7. For the following reactions, determine whether the forward or reverse reaction is favored.

a. Ag2CrO4(s) ⇌ 2 Ag+(aq) + CrO42−(aq) K = 1.1 × 10^−12

b. 2 NO(g) + O2(g) ⇌ 2 NO2(g) K = 2.5 × 10^10

c. HCN(aq) + OH−(aq) ⇌ CN−(aq) + H2O(l) K = 4.9 × 10^4

8. Write the equilibrium expression, Kp, for each of the following reactions.

a. 2 SO3(g) ⇌ 2 SO2(g) + O2(g)

b. N2(g) + O2(g) ⇌ 2 NO(g)

c. H2(g) + Cl2(g) ⇌ 2 HCl(g)

9. Write the equilibrium expression, Kc, for each of the following reactions.

a. Ag2CrO4(s) ⇌ 2 Ag+(aq) + CrO42−(aq)

b. 2 NO(g) + O2(g) ⇌ 2 NO2(g)

c. HCN(aq) + OH−(aq) ⇌ CN−(aq) + H2O(l)

10. Determine whether the following statements are true or false. Correct the false statements.

a. Equilibrium constants are ratios of the concentrations (or partial pressures) of reactants over the concentrations (or partial pressures) of products, each multiplied by the value of its coefficient in the balanced chemical reaction.

b. Solids and pure liquids are always omitted from equilibrium expressions.

c. Species dissolved into a solvent are always omitted from equilibrium expressions.

11. Explain the difference between Kc and Kp.

12. N2O4 gas dissociates into NO2 via the following reaction:

N2O4(g) ⇌ 2 NO2(aq) Kc = 6.1 × 1023 at 298 K

Calculate Kp for this reaction at 298 K.

13. SOCl2 gas dissociates into SO2 and Cl2 via the following reaction:

SOCl2(g) ⇌ SO2(g) + Cl2(g) Kp = 1.23 × 10−6 at 500 K

Calculate Kc for this reaction at 500 K.

Answer 1