C(s) + H2O(g) ⇌ CO(g) + H2 ΔH>0

Question

For the system above at equilibrium, which changes will increase the amount of H2(g)?

I. Adding C(s)
II. Increasing the volume of the container
III. Increasing the temperature

The answer is II and III. I understand everything except why II is true. Can someone please explain why increasing the volume will make more H2?!?!

Answer 1

I hope I can. Volume goes up so pressure goes down. Increase in P make the reaction shift on the side with fewer mols GAS (solids don't count). There are two mols gas on the right, 1 mol on the left so increase P makes it go to the left. Decreasing P makes it go to the right which increases H2.Hope that helps.

Answer 2

OH, thank you soo much. I forgot about the solid thing!