For the following reaction, Kp = 0.154 at a given temperature. C(s) + 2 H2(g) <=> CH4(g) At equilibrium, PCH4 = 7.9. What is the equilibrium partial pressure of H2? Give your answer to 3 significant figures.

7.16 (3  s.f)

Explanation:

C(s) + 2 H2(g) <=> CH4(g)

The formular for Kp is given as;

Kp = P CH₄ / P H₂²

When dealing with equilibrium pressures, Solids and pure liquids are omitted.

Kp = 0.154

PCH4 = 7.9

Upon solving for P H₂;

P H₂² = P CH₄ / Kp

P H₂² = 7.9 / 0.154

P H₂ =  √51.3

P H₂ = 7.16 (3  s.f)