Helmholtz free energy

Helmholtz free energy is a way of measuring energy in a system. It looks at the temperature and pressure of the system and combines it with the energy available. This helps us understand how much energy is available to do work within the system. For example, if you have a pot of boiling water, then the Helmholtz free energy will tell us how much energy is available to turn the water into steam and how much of that energy could be used to power something.