How would you calculate the heat required to change 5 pounds of ice at 32°F into water?

To determine the heat required to change 5 pounds of ice at 32°F into water, we focus on the latent heat of fusion, which is the heat required to convert a solid into a liquid at the same temperature. For ice, the latent heat of fusion is typically around 144 BTU per pound.

In this scenario, the calculation involves multiplying the mass of the ice, which is 5 pounds, by the latent heat of fusion (144 BTU/lb). This yields the total heat required to transition from ice at 32°F to water at 32°F without a temperature change. The resulting equation is:

Heat required = 5 lb × 144 BTU/lb = 720 BTU.

This approach is grounded in the principles of thermodynamics, particularly the specific heat and latent heat concepts, which illustrate how materials absorb or release heat during phase changes. The other options do not reflect the correct latent heat of fusion for ice, thus leading to incorrect total heat calculations for this phase change.