How much latent heat energy is removed when one pound of water evaporates?

The amount of latent heat energy removed when one pound of water evaporates is 970 Btu. This value represents the heat energy required for the phase change from liquid water to water vapor at a constant temperature. During evaporation, water absorbs this heat without a corresponding increase in temperature, which is why it is referred to as "latent" heat.

Understanding this concept is crucial in HVACR, as it applies to processes like cooling and dehumidification, where water absorbs heat from the surroundings to change its state and contribute to temperature regulation. The efficiency of HVAC systems often hinges on effectively managing this latent heat, particularly in maintaining indoor air quality and comfort.

The other values listed do not correctly represent the latent heat of vaporization for water at standard atmospheric conditions. Each of these amounts might pertain to different contexts, such as specific heat values for other substances or different phase changes, but they do not apply to the evaporation of water in this scenario.