Concept:A macroscopic chemical substance contains countless microscopic particles, all possessing kinetic and potential energies.
Formula:$$ U (\text{or } E) = E_{\text{kinetic}} + E_{\text{potential}} $$
Solution:- Atoms and molecules possess translational, vibrational, and rotational kinetic energies, as well as electronic and nuclear potential energies.
- The absolute sum of all these microscopic kinetic and potential energies within a defined system is known as the system's Internal energy (denoted as E or U).
Why other options are incorrect:Specific heat and heat capacity are properties measuring how temperature changes relative to added heat. Latent heat is energy associated with phase changes. None of these represent the total energy pool of the substance.
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