Question

The heat capacity of a bomb calorimeter is 500 J/^oC. When 0.1 g of a methane was burnt in this calorimeter, the temperature rose by 2^oC. The value of $\Delta \text{E}$ per mole will be

• A. $+ \text{10 kJ}$
• B. $- \text{10 kJ}$
• C. $+ \text{160 kJ}$
• D. $- \text{160 kJ}$

Answer 1

Answer: (D)

$\Delta \text{E} = - \frac{\text{M}}{\text{w}} \times \text{C} \times \Delta \text{t}$

$= - \frac{1 6}{\text{0.1}} \times 5 0 0 \times 2 = - 1 6 0 \times 1 0^{3} \text{J} = - \text{160 kJ}$ (minus sign is used as heat is evolved.)