Question

If an atom is in its ground state, has the atom the lower energy possible and there is its lower temperature?

Answer 1

By definition, an atom at its ground state has itselectrons in their lowest energy orbital configuration. When an atom is excited, an electron moves into a higher energy orbital. Light can excite atoms. Electronsmay release light at a longer wavelength if they return to the ground state in more than one step.

Answer 2

When there is an electron in the ground state (see Fig. Box 4.5A, left) and light with energy of hν comes to the electron, the electron absorbs the energy and enters the excited state. This is “absorption” of light. In contrast, when there is an electron in the exited state, the electron goes down to the ground statewith emitting light with the energy of hν . This is the “emission” of light. In Fig. Box 4.5B, energy spectra of absorption and emission are presented.