A bomb calorimeter has a heat capacity of 20.0 kJ K^-1 (including contents). Burning 1.20 g of graphite in excess oxygen (C + O2 -> CO2, Delta_cH = -393.5 kJ mol^-1; take Delta U approx Delta H here because Delta n_g = 0) raises the temperature by

JEE Main levelSingle correct optionDifficulty 2 of 3td084

A bomb calorimeter has a heat capacity of $20.0 kJ K^{- 1}$ (including contents). Burning $1.20 g$ of graphite in excess oxygen ( $C + O X_{2} CO X_{2}$ , $Δ_{c} H = - 393.5 kJ mo l^{- 1}$ ; take $Δ U \approx Δ H$ here because $Δ n_{g} = 0$ ) raises the temperature by

Amount of carbon

= 1.20/12 = 0.100 mol

, so heat released

= 0.100 \times 393.5 = 39.35 kJ

. Then

Δ T = q / C = 39.35/20.0 = 1.97 K