'); Engineering Toolbox Further, we may note that the specific heats at constant volume and constant pressure for a gas are given by: DFM DFA Training // --> The specific internal energy and the specific enthalpy of an ideal gas are dependent on temperature alone, and so equation (20.9) is valid for a gas as well as a liquid. They can be visualized in terms of the position and the velocity of objects. internal energy is internal energy per mass, and specific enthalpy is enthalpy per mass. The specific internal energy and the specific enthalpy of an ideal gas are dependent on temperature alone, and so equation (20.9) is valid for a gas as well as a liquid. They can be visualized in terms of the position and the velocity of objects. internal energy is internal energy per mass, and specific enthalpy is enthalpy per mass.