The alkali metals belong to Group 1 of the periodic table, and they include elements such as lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr). The general valence-electron ground-state electron configuration for neutral alkali metals is ns^1, where "n" represents the principal quantum number corresponding to the energy level of the outermost electron.
For example:
- Lithium (Li): The atomic number of lithium is 3. Its electron configuration is 1s^2 2s^1, and the valence electron configuration is 2s^1.
- Sodium (Na): The atomic number of sodium is 11. Its electron configuration is 1s^2 2s^2 2p^6 3s^1, and the valence electron configuration is 3s^1.
- Potassium (K): The atomic number of potassium is 19. Its electron configuration is 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1, and the valence electron configuration is 4s^1.
This pattern continues for other alkali metals as well, where the outermost electron occupies the "s" orbital in the highest energy level (shell) of the atom.