Question

module 4: electrons in atoms test - 11/14/2025
as an atom in the ground state changes to an atom in an excited state, the atom__________.
○ increases in mass number.
○ absorbs energy.
○ decreases in mass number.
○ releases energy.

Explanation:

When an atom changes from the ground state (lowest - energy state) to an excited state (higher - energy state), it needs to gain energy. Mass number is related to the number of protons and neutrons in the nucleus and is not affected by electron excitation (since only electrons are involved in the ground - to - excited state transition, not protons or neutrons). Releasing energy would be the case when an atom goes from an excited state to a ground state.

Answer:

absorbs energy.