One tablespoon of peanut butter has a mass of 16 g . It is combusted in a calorimeter whose heat capacity is 110 kJ/∘C . The temperature of the calorimeter rises from 22.1 ∘C to 25.4 ∘C.

Question

Part A
Find the food caloric content of peanut butter.
Express your answer using two significant figures.

Answer 1

I assume that when you say food calories you want kcal/g.
q for 15 g peanut butter = Ccal x delta T
q = 110 kJ/C x (25.4 - 22.1) = 363 kJ for 15 g p butter or
363 kJ/15 g = 24.2 kJ/g
24.2 kJ x (1,000 J/kJ) x (1 cal/4.184 J) x (1 kcal/1,000cal) = ? food cal