Question

A gobar gas plant produces methane and supplies to the families. If a family requires 15,000 KJ of energy per day, how many days will the quota of 10 Kg will last. $({△}_{c}Hof{CH}_4=-1665KJ{mol}^{-1})$.

Answer 1

Given: Heat of combustion $=-1665KJ/mol=-1665\times {10}^{4}J/mol$

Molecular mass of Methane $\left(C{H}_4\right)=12+4=16g/mol$

$1$ mole or $16g$ of methane on complete combustion give $=1665\times {10}^{3}J/mol$

$10kg$ or $10000g$ of $C{H}_4$ on complete combustion give $\frac{1665\times {10}^3\times 10000}{16}=1040625KJ$

But family need $15000KJ$ of energy per day.

Hence number of day $=\frac{1040625}{15000}=69days$