The reactions shown here can be combined to make the overall reaction
C(s) + H₂O(g) ⇌ CO(g) + H₂(g) by reversing some and/or dividing all the coefficients by a number.
a. C(s) + O₂ (g) → CO₂ (g) K = 1.363 × 10⁶⁹
b. 2 H₂(g) + O₂ (g) →2 H₂O (g) K = 1.389 × 10⁸⁰
c. 2CO(g) + O₂ (g) → 2 CO₂ (g) K = 1.477 × 10⁹⁰