Question

When 5.0 moles of butane react completely?

Answer 1

Moles of Carbondioxide-CO₂ produced = 20 moles

Further explanation

The combustion of hydrocarbons with excess oxygen will produce carbon dioxide and water(CO₂+H₂O), whereas if there is not much oxygen, carbon monoxide and water(CO+H₂O) will be obtained.

The reaction coefficient in a chemical equation shows the mole ratio of the reacting compounds

Reaction (combustion of butane) :

2C₄H₁₀+13O₂⇒8CO₂+10H₂O

Butane reacts completely, then Butane is the limiting reactant and oxygen as the excess reactant, so the moles of Carbon dioxide are based on the butane moles as the limiting reactant.

moles of butane - C₄H₁₀ = 5 moles

From the reaction, the mol ratio of C₄H₁₀ and CO₂ : 2 : 8, so mol CO₂ :

$\tt \dfrac{8}{2}\times 5~moles=20~moles$