The question lacks some details in order to be answered. Nevertheless, let's just give some examples. Given that you are to burn 10 kg of methane (CH4) from 0 to 20°C. The specific heat capacity of methane is 4.475 kJ/kg-K.
H = mCpT H = (10kg)( 4.475 kJ/kg-K)(20-0) H = 895.00 kJ Because of the positive value of enthalpy, methane takes in heat.
