1. Given that Kc = 1.6×10^-34 at 25 °C for this reaction: 2 HCl(g) + I₂ (s) ?2 HI(g) + Cl₂ (g)

a. What is K at 25 °C for the same reaction?

Determine the value of Kc for each of the following reactions:

b. 2 HI(g) + Cl₂ (g) ? 2 HCl(g) + I₂ (s)

c. 4 HCl(g) + 2 I₂ (s) ?3 HI(g) + 2 Cl₂ (g)

d. HI(g) + ½ Cl₂ (g) ? HCl(g) + ½ I₂ (s)

2. Find Kp for this reaction: N₂O(g) + NO₂ (g) ? 3 NO(g)

Given: N₂ (g) + O₂ (g) ? 2 NO(g) Kp = 2.3×10^-3

2 NO(g) + O₂ (g) ? 2 NO₂ (g) Kp = 7.4×10^-6

2 N₂O(g) ? 2 N₂ (g) + O₂ (g) Kp = 1.9×10¹¹

3. Consider the following system at equilibrium:

2 PbS(s) + 3O₂ (g) ? 2 PbO(s) + 2 SO₂ (g) ?H°= -827.4 kJ

For each of the following changes

(1) Would the equilibrium yield of PbO increase, decrease, or remain unchanged? Explain.

(2) Would the value of the equilibrium constant increase, decrease, or remain unchanged? Explain.

a. increasing PO₂ d. increasing the volume

b. adding SO₂ to the system e. increasing the total pressure by adding argon

c. decreasing the temperature f. adding a catalyst

4. When carbon monoxide reacts with hydrogen gas, methane and steam are formed:

CO(g) + 3 H₂ (g) ? CH₄ (g) + H₂O(g)

At 1127 °C, analysis at equilibrium shows the presence of 0.0321 mol CO, 0.0421 mol H₂, 0.00136 mol CH₄ and 0.000432 mol H₂O in a 4.00 liter container.

a. Calculate K_c for this reaction at 1127 °C. 

b. Calculate K_p for this reaction at 1127 °C. 

5. Consider the reaction between ammonia and oxygen:

4 NH₃ (g) + 3 O₂ (g) ? 2 N₂ (g) + 6 H₂O(g)

At a certain temperature, K_p = 0.0049. Calculate the equilibrium partial pressure of ammonia if (PN₂)E = 0.213 atm, (P_H2O )E = 0.883 atm and (P_O2)E = 0.255 atm.

6. Determine the equilibrium constant for this reaction: 2 NO₂ Cl(g) ? Cl₂ (g) + 2 NO₂ (g)

The container is initially charged with 0.2231 atm of NOCl and 0.1468 atm of Cl , and at equilibrium, the pressure of NO₂ is 0.1866 atm.

Pure hydrogen cyanide, at 0.120 M is placed into a sealed vessel and heated to 375 K. When the system reaches equilibrium, it is found that 33.0% of the hydrogen cyanide has decomposed to cyanogen (C N ) and hydrogen:

2 HCN(g) ? C₂N₂ (g) + H₂ (g)

Calculate K_c for this reaction at 375 K.

7. At 100 °C, Kc = 0.07800 for this reaction: SO₂Cl₂ (g) ? SO₂ (g) + Cl₂ (g)

Suppose initially [SO₂Cl₂ ] = 0.2000 M, [SO ] = 0.3000 M, and [Cl ] = 0.9500 M.

a. Will the reaction go left or right to reach equilibrium?

b. What are the equilibrium concentrations of all species?

8. At 150 °C, K_c = 0.00850 for this reaction: 2 IBr(g) ? I₂ (g) + Br₂ (g)

Pure IBr is placed into a 4.00 L vessel. At equilibrium, the concentration of Br₂ is 0.0245 M. How many grams of IBr were initially put into the vessel?