Question

A sample of octane (c8h18 that has a mass of 0.750 g is burned in a bomb calorimeter. as a result, the temperature of the calorimeter increases from 21.0°c to 41.0°c. the specific heat of the calorimeter is 1.50 j/(g °c, and its mass is 1.00 kg. how much heat is released during the combustion of this sample? use .

Answer 1

30 kJ is released during the combustion of this sample.

Step-by-step explanation:

Heat released during combustion = Heat gained by calorimeter

Mass of calorimeter= m = 1.00 kg=1000 g

Change in temperature of the calorimeter = ΔT = 41.0 °C - 21.0 °C =20.0 °C

Specific heat if calorimeter = c = 1.50 J/g °C

Heat released during combustion = Q

`Q=mc\Delta T`

`Q=1000.00 g* 1.50 J/g ^oC* 20.0 ^oC=30,000 =30 kJ`

30 kJ is released during the combustion of this sample.

Answer 2

In a closed system, heat should be conserved which means that the heat produced in the calorimeter is equal to the heat released by the combustion reaction. We calculate as follows:

Heat of the combustion reaction = mC(T2-T1)
= 1 (1.50) (41-21)
= 30 kJ