Question 1:

A mixture of water and graphite is heated to 890 K in a 10 L container. When the system comes to equilibrium it contains 0.875 mol each of CO and H₂ and 0.289 mol of H₂O and some graphite. Some O₂ is added to the system and a spark is applied so that the H₂ reacts completely with the O₂ forming H₂O. Find the amount of CO in the flask when the system returns to equilibrium.

Question 2:

Consider the reaction:

2 H₂S (g) + SO₂ (g) ↔ 3S (s) + 2 H₂O (g)

A reaction mixture initially containing 0.600 bar each of H₂S and SO₂ was found to contain 0.0054 bar of H₂O at equilibrium at 1300 K. A second reaction mixture at the same temperature initially contains 0.500 bar of H₂S and 0.350 bar of SO₂. Calculate the equilibrium concentrations of all reactants and products at equilibrium.

Question 3:

Hydrogen can be extracted from natural gas according to the reaction:

CH₄(g) + CO₂(g) ↔ 2 CO (g) + 2 H₂ (g) K = 4.5 x 102 at 1115 K

An 85.0 L reaction container initially contains 22.3 kg of CH₄ and 55.4 kg of CO₂ at 1115 K. Assuming ideal gas behaviour, calculate the mass of H₂ (in g) present in the reaction mixture at equilibrium. What is the percent yield of the reaction under these conditions?

Question 4:

The equilibrium constant for the reaction SO₂ (g) + NO₂ (g) ↔ SO₃ (g) + NO (g) is 15.6 at 1000 K. Find the amount of NO2 that must be added to 2.4 mol of SO₂ in order to form 1.2 mol of SO₃ at equilibrium.

Question 5:

Solid carbon can react with gaseous water to form carbon monoxide gas and hydrogen gas. The equilibrium constant for the reaction at 700 K is K_p = 1.60 x 10^-3. If a 1.55 L reaction vessel initial contains 145 mbar of water at 700.0 K in contact with excess solid carbon, find the percent by mass of hydrogen gas of the gaseous reaction mixture at equilibrium.