Five mol of calcium carbide are combined with 10 mol of water in a closed, rigid, high-pressure vessel of 1800 cm3 internal empty volume. Acetylene gas is produced by the reaction:

CaC₂  +  2H₂O  →  C₂H₂  + Ca(OH)₂

Explanation:

In order to find out the reaction, we must know the reactants.

For this situation, we make acetylene gas from carbide calcium CaC₂ and H₂O (water); therefore the reactants are:

- CaC₂  and  H₂O

Acetylene is one of the products made  →  C₂H₂

So the reaction can be formed as this:  CaC₂  +  H₂O  →  C₂H₂

We missed the calcium, and this reaction also makes, Calcium Hydroxide, so the complete equation must be:

CaC₂  +  H₂O  →  C₂H₂  + Ca(OH)₂

This is unbalanced, because we have 1 O in left side and 2 in right side so we add 2 in water so now, we get the complete reaction:

1 mol of calcium carbide reacts to 2 mol of water in order to produce 1 mol of acetylene and 1 mol of calcium hydroxide.