Final answer:
Enthalpy is the total energy content of a system, defined as the sum of the system's internal energy and the product of its pressure and volume.
Step-by-step explanation:
Enthalpy is the total energy content of a system. It is defined as the sum of the system's internal energy and the product of its pressure and volume. Enthalpy is a state function, meaning that it only depends on the initial and final states of the system and not on the path taken to reach those states.