A slice of pizza has 500 kcal.If we could burn the pizza and use all the heat to warm a 50-L container of cold water,what would be the approximate increase in the temperature of the water? (Note: A liter of cold water weighs about 1 kg. )

Question

Quizplus · Accepted Answer

We can use the formula Q = mcΔT, where Q is the heat transferred, m is the mass of the water, c is the specific heat capacity of water, and ΔT is the change in temperature.

Since we have 50 L of water, its mass would be 50 kg (1 L = 1 kg). The specific heat capacity of water is approximately 4.18 J/g°C.

To find the heat transferred from the pizza to the water, we can convert the 500 kcal to joules:

500 kcal = 2092000 J

Assuming all this heat is transferred to the water, we can calculate the change in temperature:

2092000 J = 50 kg x 4.18 J/g°C x ΔT

ΔT = 100°C / (50 kg x 4.18 J/g°C)

ΔT ≈ 4.77°C

Therefore, the approximate increase in the temperature of the water would be 4.77°C, which is closest to Choice D, 10°C. However, note that this answer assumes 100% heat transfer efficiency, which is not realistic in practice.

A Slice of Pizza Has 500 Kcal