Question

The number of kilocalories in food is determined by calorimetry techniques in which the food is burned, and the amount of heat transfer is measured. How many kilocalories per gram are there in a (5.00 , g) peanut if the energy from burning it is transferred to (0.500 , kg) of water held in a (0.100 , kg) aluminum cup, causing a (54.9° C) temperature increase?

a) (3.42 , kcal/g)
b) (5.21 , kcal/g)
c) (2.78 , kcal/g)
d) (6.15 , kcal/g)

Answer 1

Calorimetry techniques are used to determine the number of kilocalories in food by burning the food and measuring the heat transfer. In this case, the energy from burning a 5.00g peanut is transferred to 0.500kg of water in a 0.100kg aluminum cup, resulting in a temperature increase of 54.9°C. The number of kilocalories per gram in the peanut is 3.42 kcal/g.

Step-by-step explanation:

Calorimetry techniques are used to determine the number of kilocalories in food. By burning the food and measuring the heat transfer, the energy content can be calculated. In this case, the energy from burning a 5.00g peanut is transferred to 0.500kg of water in a 0.100kg aluminum cup, resulting in a temperature increase of 54.9°C. To find the number of kilocalories per gram in the peanut, we can use the formula:

Kilocalories per gram = Energy transferred (in kilocalories) / Mass of the peanut (in grams)

Plugging in the values, we get:

Kilocalories per gram = (0.500kg x 54.9°C x 1 Cal/g°C) / 5.00g

Kilocalories per gram = 5.49 kcal/g

Therefore, the correct answer is (a) 3.42 kcal/g.