How many BTUs are required to vaporize one pound of water?

The vaporization of water requires a significant amount of energy to convert the liquid into vapor without changing its temperature. This energy is measured in British Thermal Units (BTUs). To vaporize one pound of water, 970 BTUs are needed. This value represents the latent heat of vaporization, which is the energy required to turn a substance from a liquid into a vapor at its boiling point.

Understanding this concept is crucial, especially in the context of heating systems and energy calculations. The high energy requirement highlights the efficiency and energy costs associated with boiling water, which is important knowledge for operating engineers involved in HVAC systems or steam generation. The other options do not accurately reflect the energy necessary for this process, making the selection of 970 BTUs the correct and relevant choice in the context of this question.