Which temperature requires approximately 561 BTUs for the transformation of 1 pound of ammonia?

The transformation of ammonia involves understanding its phase changes and the energy required for these processes. The specific answer to this question is based on the latent heat of vaporization and the specific heat of the substance.

For ammonia, at 32°F (the freezing point of water), it is at a critical temperature for phase changes. To transform one pound of ammonia starting from a temperature below freezing into a gaseous state requires approximately 561 BTUs. This amount of energy is sufficient to overcome the intermolecular forces and facilitate the transition from liquid to vapor while considering the specific properties of ammonia at this temperature.

Other temperatures in the options provided do not correlate to this specific energy requirement for one pound of ammonia. For instance, temperatures significantly below or above 32°F would have different energy requirements based on their respective heat capacities and states (solid, liquid, gas), making 32°F the temperature that fits the context of the required transformation and energy input as described.