Final answer:
When a molecule is exposed to ultraviolet (UV) light, it undergoes electronic transitions. Infrared (IR) light causes molecules to undergo vibrational transitions. Microwaves primarily affect the rotational motion of molecules.
Step-by-step explanation:
When a molecule is exposed to ultraviolet (UV) light, it can undergo electronic transitions where one of its electrons jumps from a lower energy to a higher energy molecular orbital. This results in the molecule becoming excited and potentially undergoing chemical reactions.
Infrared (IR) light interacts with molecules by causing them to undergo vibrational transitions. The thermal motion and vibration of atoms and molecules produce infrared radiation, and when molecules absorb this type of light, they experience changes in their vibrational energy levels.
Microwave radiation has the lowest energy in the electromagnetic spectrum, and it primarily affects the rotational motion of molecules. When water molecules in food are exposed to microwave radiation, they absorb the photons and increase their rotational energies, resulting in the generation of heat and cooking of the food.