What is the sum of energy in a substance called?

What is the sum of energy in a substance called?

• A. Internal Energy
• B. Kinetic Energy
• C. Potential Energy
• D. Thermal Energy

Answer: (A)

Internal energy is the energy content of a substance stored in its microscopic motions and interactions. It includes the random motion of molecules (their microscopic kinetic energy) and the forces between molecules (intermolecular potential energy). This is the energy that changes when you heat or cool the substance or compress it, and it excludes energy associated with the whole substance moving as a single object (bulk kinetic energy) or its position in a field (bulk potential energy). While some texts use the term thermal energy loosely to mean the same idea, the precise thermodynamic quantity that represents the sum of microscopic energies is internal energy.

Internal energy is the energy content of a substance stored in its microscopic motions and interactions. It includes the random motion of molecules (their microscopic kinetic energy) and the forces between molecules (intermolecular potential energy). This is the energy that changes when you heat or cool the substance or compress it, and it excludes energy associated with the whole substance moving as a single object (bulk kinetic energy) or its position in a field (bulk potential energy). While some texts use the term thermal energy loosely to mean the same idea, the precise thermodynamic quantity that represents the sum of microscopic energies is internal energy.