How many moles of hydrogen gas would be needed to react with excess carbon dioxide to produce 42.1 moles of water vapor?

84.2 mol hydrogen gas (H₂) woiuld be needed to react with excess carbon dioxide to produce 42.1 moles of water vapor.

Explanation:

1) Word equation:

hydrogen (g) + carbon dioxide (g) → water (g) + methane (g)

2) Molecular equation:

H₂(g) + CO₂(g)→ H₂O(g) + CH₄(g)

3) Balanced molecular equation:

4H₂(g) + CO₂(g)→ 2H₂O(g) + CH₄ (g)

4) Stoichiometric mole ratios:

4 mol H₂ : 1 mol CO₂ : 2 mol H₂O(g) : 1 mol CH₄

5) Set a proportion with the stoichiometric mole ratios, the moles of water vapor produced and the unknown:

4 mol H₂ / 2 mol H₂O = x / 42.1 mol H₂O  

     ⇒ x = 42.1 mol H₂O × 4 mol H₂ / 2 mol H₂O = 84.2 mol H₂ ← answer

Enzyme make a hormone as a catalyst

Ithink that the answer is b