AMU Engineering 2020 solved paper Solved Paper

Molar mass of ethanol (CH3CHO)
‌‌=12+(3×1)+12+1+(16×1)
‌‌=12+3+12+1+16=44
Heat of combustion is the heat produced due to combustion of 1mol(44g) of ethanol.
As xg of ethanol give yJ of heat energy
∴44g of ethanol gives heat energy =‌

y×44

x

Jmol−1
As combustion is an exothermic process.
Heat of combustion of ethanol =−‌

y

x

×44Jmol−1