Question

1 g sample of octane c8h18c8h18 is burned in excess of oxygen in a bomb calorimeter. The temperature of the calorimeter rises from 294 k to 300 k. If heat capacity of the calorimeter is 8 kj/k, the enthalpy of combustion of octane is

Answer 1

Heat energy produced = 1*8*(300-294) = 48J

Number of moles of octane = 1/12*8+1*18 = 0.0087mol

Enthalpy change = 48/0.0087 = 6000/1000= 6kJmol^-1

(Hope, I was able to help :) )