4.184g of benzoic acid was burnt in bomb calorimeter. The rise in the temperature is `10^@`. The heat capacity of calorimeter and its contents is `2.644 kcal K^(-1)`. Calculate the heat of combustion of benzoic acid. 

Explanation

The heat of combustion = `-(h xx q xx M)//m`
  Rise in temperature of calorimeter and its contents, `theta = 10^@ `
The heat capacity of calorimeter and its contents, `h = 2.644 xx 4.184 J K^(-1)`. The inass of combustible substance, (benzoic acid), `m = 4.184g`. The molar mass of benzoic acid, `M = 122g mol^(-1)`.
The heat of combustion of benzoic acid
`= (2.644 xx 4.184 xx 10 xx122)/(4.184) = -3226 kJ mol^(-1)`