Mothballs are composed primarily of the hydrocarbon naphthalene (c10h8). when 1.025 g of naphthalene is burned in a bomb calorimeter, the temperature rises from 24.25 ∘c to 32.33 ∘c. find δerxn for the combustion of naphthalene. the heat capacity of the calorimeter, determined in a separate experiment, is 5.11kj/∘c.

for combustion of naphthalene is -5164 kJ/mol

Explanation:

where, C refers heat capacity and refers change in temperature.

Here,

So,

is generally expressed in terms of per mole unit of reactant. Also, should be negative as it is an exothermic reaction (temperature increases).

Molar mass of naphthalene is 128.17 g/mol

So, 1.025 g of naphthalene = of naphthalene

                                              = 0.007997 moles of naphthalene