Question

A researcher studying the nutritional value of a new candy places a 4.40 g sample of the candy inside a bomb calorimeter and combusts it in excess oxygen. The observed temperature increase is 2.32 'C. If the heat capacity of the calorimeter is 43.40 kJ K , how many nutritional Calories are there per gram of the candy? Calories per gram of candy: Cal/g

Answer 1

Given:
C = 43.40 KJ/K = 43.40 KJ/oC
delta T = 43.40 oC

Energy released,
Q = Ccal*delta T
= 43.40 KJ/oC * 43.40 oC
= 100.688 KJ

1 nutritional calorie = 4.184 KJ

Converting this energy to nutritional calorie

Q = 100.688 KJ / 4.184 KJ/Cal
= 24.065 Cal

This is for 4.40 g

so,
nutritional calorie per gram = 24.065 Cal/4.40 g
= 5.47 Cal/g

Answer: 5.47 Cal/g