Question

A 6.55 g sample of aniline (C_{6}H_{5}NH_{2}, molar mass = 93.13 g/mol) was combusted in a bomb calorimeter. If the temperature rose by 32.9°C, use the information below to determine the heatcapacity of the calorimeter.

Answer 1

This is an incomplete question, here is a complete question.

A 6.55 g sample of aniline
`(C_6H_5NH_2)` molar mass = 93.13 g/mol) was combusted in a bomb calorimeter. If the temperature rose by 32.9°C, use the information below to determine the heat capacity of the calorimeter.

`4C_6H_5NH_2(l)+35O_2(g)\rightarrow 24CO_2(g)+14H_2O(g)+4NO_2(g)`

ΔH°rxn = -1.28 × 10⁴ kJ

Answer : The heat capacity of the calorimeter is,
`6.84kJ/^oC`

Explanation :

First we have to calculate the moles of aniline.

`\text{Moles of aniline}=\frac{\text{Mass of aniline}}{\text{Molar mass of aniline}}`

`\text{Moles of aniline}=(6.55g)/(93.13g/mol)`

`\text{Moles of aniline}=0.0703mol`

Now we have to calculate the heat releases.

As, 4 mole of aniline on combustion to releases heat =
`1.28* 10^4kJ`

So, 0.0703 mole of aniline on combustion to releases heat =
`(0.0703)/(4)* 1.28* 10^4kJ=224.96kJ`

Now we have to calculate the heat capacity of the calorimeter.

`\text{Heat capacity of the calorimeter}=\frac{\text{Heat releases}}{\text{Change in temperature}}`

`\text{Heat capacity of the calorimeter}=(224.96kJ)/(32.9^oC)`

`\text{Heat capacity of the calorimeter}=6.84kJ/^oC`

Thus, the heat capacity of the calorimeter is,
`6.84kJ/^oC`