A sample of n-octane $(1.14 \mathrm{~g})$ was completely burnt in excess of oxygen in a bomb calorimeter, whose heat capacity is $5 \mathrm{~kJ} \mathrm{~K}^{-1}$. As a result of combustion reaction, the temperature of the calorimeter is increased by 5 K. The magnitude of the heat of combustion of…

Question

A sample of n-octane $(1.14 \mathrm{~g})$ was completely burnt in excess of oxygen in a bomb calorimeter, whose heat capacity is $5 \mathrm{~kJ} \mathrm{~K}^{-1}$. As a result of combustion reaction, the temperature of the calorimeter is increased by 5 K. The magnitude of the heat of combustion of octane at constant volume is ______ $\mathrm{kJ} \mathrm{mol}^{-1}$ (nearest integer).

Aicharya · Accepted Answer

$	ext { Mole of octane }=\frac{1.14}{114}=0.01 \mathrm{~mole}$ Heat evolved $=\mathrm{C} 	imes \Delta \mathrm{T}$ $\begin{aligned} & =5 	imes 5 \mathrm{~kJ} \ & =25 \mathrm{~kJ} \end{aligned}$ $	herefore$ Magnitude of Heat of combustion $=\frac{25}{0.01}=2500$ $\mathrm{kJ} /$ mole

A sample of n-octane $(1.14 \mathrm{~g})$ was completely burnt in excess of oxygen in a bomb calorimeter,…

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