Question

A researcher studying the nutritional value of a new candy places a 6.90-gram sample of the candy inside a bomb calorimeter and combusts it in excess oxygen. The observed temperature increase is 2.40 °C. If the heat capacity of the calorimeter is 37.30 kJ·K–1, how many nutritional Calories are there per gram of the candy?

Answer 1

Increase in temperature = 2.4 oC = 2.4 K
C = 37.30 kJ·K–1

q = C* delta T
    =37.30 kJ·K–1 * 2.4 K
    =89.52 KJ

m = 6.90 g

Heat released be gram = 89.52 KJ / 6.9 g
                                               = 12.97 KJ/g
                                               = 12.97/4.186 Kcal/g
                                               = 3.099 Kcal/g

1 Cal = 1 Kcal
Cal is food calorie and cal is unit of energy

Answer is 3.099 Cal