Question

A 6.0 kg zinc cannonball has been sitting in the desert sun all day. Its temperature is 35 °C. Night falls on the desert, and the temperature falls to a chilling -10.0 °C. How much heat will the cannonball release as it cools to thermal equilibrium with the air?

Answer 1

The zinc cannonball will release 1,053,000 Joules of heat energy as it cools from 35°C to -10.0°C.

Step-by-step explanation:

To calculate the amount of heat released by the zinc cannonball as it cools, we can use the formula:
Q = mcΔT, where Q is the heat energy, m is the mass, c is the specific heat capacity of the substance, and ΔT is the change in temperature.

For zinc, the specific heat capacity (c) is approximately 0.39 J/g°C. The mass (m) of the cannonball is given as 6.0 kg (6000 g), and the change in temperature (ΔT) is from 35°C to -10.0°C, a difference of 45.0°C (since ΔT = T_final - T_initial and T_initial > T_final, it’s a negative value indicating an exothermic process).

The formula becomes: Q = (6000 g)(0.39 J/g°C)(-45.0°C).
Thus, Q = -1053000 J, which means the cannonball releases 1,053,000 Joules, or 1.053 MJ of heat energy as it cools down.