16. Chemical Equilibrium

The equilibrium constant, K, for 2 NO (g) + O₂ (g) ⇌ 2 NO₂ (g) is 6.9 x 10². 

What is the [NO] in an equilibrium mixture of gaseous NO, O₂, and NO₂ at 500 K that contains 1.5 x 10 ^–2 M O₂ and 4.3 x 10 ^–3 M NO₂?

The decomposition of nitrogen monoxide can be achieved under high temperatures to create the products of nitrogen and oxygen gas. 

6 NO(aq) ⇌ 3 N₂(aq) + 3 O₂(aq) 

a) What is the equilibrium equation for the reaction above?

b) What is the equilibrium expression for the reverse reaction. 

CH₄ (g) + 2 H₂S (g) ⇆ CS₂ (g) + 4 H₂ (g)

Methane (CH₄) reacts with hydrogen sulfide to yield hydrogen gas and carbon disulfide, a solvent used in the manufacturing rayon and cellophane. What is the value of K_c at 1000 K if the partial pressures in an equilibrium mixture at 1000 K are 0.20 atm methane, 0.15 atm hydrogen sulfide, 0.30 atm carbon disulfide and 0.10 atm hydrogen gas? 

CH₄ (g) + 2 H₂S (g) ⇌ 4 H₂ (g) + CS₂ (g)