Question

A 2.64 g sample of hydroquinone (C6H6O2) was combusted in a bomb calorimeter. 234 joules of energy was generated. The temperature rose from 25.0°C to 34.9°C. Calculate the heat capacity, molar heat capacity and the specific heat capacity.

Answer 1

molar mass of hydroquinoine = 110 g/mole.

2.64 gm sample of hydroquinone =mass / molar mass = 2.64 / 110 = 0.024 mole.

we know,

heat capacity = energy / dT = 234 / (34.9 - 25.0) = 23.6 J/oC.

let molar heat capacity is s1 J/mole-oC.

Heat = m1 * s1 * dT

234 = 0.024 * s1 * (34.9 - 25.0)

s1 = 984.8 J/mole-oC

so molar heat capacity is 984.8 J/mole-oC.

let specific heat capacity = s2 J/gm-oC

Heat = m2 * s2 * dT

234 = 2.64 * s2 * (34.9 - 25.0)

s2 = 8.95 j/gm-oC

so specific heat capacity is 8.95 J/gm-oC.