What does 'l' in the formula H = ml refer to?

In the formula H = ml, the 'l' represents the latent heat. This context pertains to thermodynamics, where 'H' refers to the total heat energy involved in a phase change, and 'm' signifies the mass of the substance undergoing this change. Latent heat refers specifically to the amount of heat absorbed or released by a substance during a phase transition, such as melting or boiling, without a change in temperature.

Understanding this definition helps clarify that 'l' is not referring to length, weight, or temperature, as those concepts do not directly relate to the heat energy involved in phase changes. Instead, latent heat is a critical concept in calculating energy requirements for these processes, making it the correct reference in the formula.