Question

The heat of combustion of sucrose (C12H22O11) is 1350 kcal. How much of heat will be liberated when 17.1 g of sucrose is burnt ?

• A. 67.5 kcal
• B. 13.5 kcal
• C. 40.5 kcal
• D. 25.5 kcal

Answer 1

Answer: (A)

67.5 kcal

Answer 2

Heat evolved from 1 mole of sucrose (342 g) = 1350 kcal

Heat evolved from 17.1 g of sucrose = $\frac{1350}{342} \times 17.1 = 67.5$ kcal.