Final answer:
The energy possessed by molecules is primarily kinetic and potential energy, with thermal energy being the form related to the random motion of molecules, and chemical energy being a type of potential energy stored in chemical bonds.
Step-by-step explanation:
The molecular energy possessed by molecules is primarily in the form of kinetic and potential energy. However, when referring specifically to the energy associated with the random motion of molecules, this is known as thermal energy. Kinetic energy (KE) is directly related to the energy of motion and increases with the velocity of the molecules. Thermal energy is a subcategory of internal energy and corresponds to the average kinetic energy of a substance's molecules. The temperature of a substance is a direct measure of the thermal energy it contains.
Atoms and molecules in motion possess kinetic energy, and this energy can also manifest as thermal energy when considering the random, thermalized movement of these particles. Potential energy, on the other hand, is energy due to position, composition, or condition, such as the energy stored in chemical bonds. Chemical energy, which is a type of potential energy, is associated with the particular arrangement of atoms in a chemical compound, and changes during chemical reactions.