Answer to Question #297165 in General Chemistry for lacey

Question

1) At a particular temperature k= 6.7x10^-6 for the following reaction:

2Br2(g) +O2(g) -> 2Br2O(g)

In an experiment in which 1.0 mol of Br2 and 1.0 mol of O2 are mixed in a 2.5-L vessel, what are the equilibrium concentrations of all gases?

2) At a particular temperature k= 6.5x10^-6 for the following reaction:

2Cl2(g)+O2(g) -> 2Cl2O(g)

In an experiment in which 2.0 mol of Cl2 and 1.5 mol of O2 are mixed in a 2.0-L vessel, what are the equilibrium concentrations of all gases?

Answer 1

1) 2Br₂(g) + O₂(g) -> 2Br₂O(g)

k = [Br₂O]²/[O₂][Br₂]²

C₀(Br₂O) = 0 mol/L

C₀(O₂) = 1 mol / 2.5 L = 0.4 mol/L

C₀(Br₂) = 1 mol / 2.5 L = 0.4 mol/L

[Br₂O] = 2x mol/L

[O₂] = (0.4 - x) mol/L

[Br₂] = (0.4 - 2x) mol/L

6.7 x 10^-6 = (2x)²/(0.4 - x)(0.4 - 2x)²

x = 0.52 x 10^-3 mol/L

[Br₂O] = 0.001 mol/ L

[O₂] = 0.399 mol/L

[Br₂] = 0.399 mol/L

2) 2Cl₂(g) + O₂(g) -> 2Cl₂O(g)

k = [Cl₂O]²/[O₂][Cl₂]²

C₀(Cl₂O) = 0 mol/L

C₀(O₂) = 1.5 mol / 2.0 L = 0.74 mol/L

C₀(Cl₂) = 2.0 mol / 2.0 L = 1.0 mol/L

[Cl₂O] = 2x mol

[O₂] = (0.74 - x) mol/L

[Cl₂] = (1.0 - 2x) mol/L

6.5 x 10^-6 = (2x)²/(0.74 - x)(1.0 - 2x)²

x = 1.1 x 10^-3 mol/L

[Cl₂O] = 0.0022 mol/ L

[O₂] = 0.739 mol/L

[Cl₂] = 0.999 mol/L