Here's why:
* Ground State: The ground state is the lowest energy level an electron can occupy in an atom.
* Excited State: When an electron absorbs energy, it jumps to a higher energy level, called an excited state.
* Radiation and Energy Levels: The energy of the absorbed radiation must precisely match the energy difference between the ground state and the specific excited state the electron transitions to.
Think of it like this: Imagine the electron is on a ladder. The ground state is the bottom rung. When it absorbs radiation, it's like climbing up the ladder to a higher rung – an excited state.
Important Note: The excited state is unstable. The electron will eventually return to the ground state, releasing the absorbed energy as light or other forms of radiation. This is the basis for atomic emission spectroscopy.
