Here's a breakdown:
* n represents the principal quantum number, which indicates the energy level of the electron.
* s represents the orbital type, which is a spherical orbital.
* ¹ indicates that there is one electron in the s orbital.
Example:
* Lithium (Li): 1s² 2s¹
* Sodium (Na): 1s² 2s² 2p⁶ 3s¹
* Potassium (K): 1s² 2s² 2p⁶ 3s² 3p⁶ 4s¹
* Rubidium (Rb): 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰ 4p⁶ 5s¹
As you can see, each element has a single electron in its outermost s orbital. This configuration is responsible for their similar chemical properties, making them all highly reactive alkali metals.
