K_p and the reverse of steam reforming.

The reverse of steam reforming is an exothemic process

CO(g) + 3H₂(g) CH₄(g) + H₂O(g) Δ_rH = –206 kJ mol⁻¹

The equilibrium constant, K_p, for this reaction, at 25 ^oC
is (8.6 × 10⁻²⁶)⁻¹ = 1.6 × 10²⁵, far to the right.
At 325 ^oC, K_p = 5 × 10⁶, smaller but still well to the right.
this is made use of to remove traces of carbon monoxide, CO,
from the gas stream of hydrogen, H₂ used with nitrogen, N₂
in the Haber process to make ammonia.