Answer to Question #211121 in Chemistry for sara

Question

Consider the following equilibrium:

CH4 + H2O = CO + 3H2      Keq = 5.67 

An equilibrium mixture of this system was found to contain the following concentrations: 

[CH4] = 0.59 M, [H2O] = 0.63 M, [CO] = 0.25 M

What was the equilibrium [H2]?

Answer 1

Solution:

Balanced chemical equation:

CH₄ + H₂O → CO + 3H₂

The equilibrium expression for the reaction system:

K_eq = 5.67

[CH₄] = 0.59 M

[H₂O] = 0.63 M

[CO] = 0.25 M

[H₂] = unknown

Therefore,

[H₂]³ = (5.67 × 0.59 × 0.63) / (0.25) = 8.43

[H₂] = (8.43)^1/3 = 2.035

[H₂] = 2.035 M

Answer: [H₂] = 2.035 M