1s² 2s² 2p⁶ 3s² 3p¹

Here's how to break it down:

* 1s²: The first energy level (n=1) has one subshell, the "s" subshell, which holds 2 electrons.

* 2s²: The second energy level (n=2) has two subshells, "s" (holds 2 electrons) and "p" (holds 6 electrons).

* 2p⁶: The "p" subshell in the second energy level is filled with 6 electrons.

* 3s²: The third energy level (n=3) starts with the "s" subshell, holding 2 electrons.

* 3p¹: The "p" subshell in the third energy level has only 1 electron.

Simplified notation: You can also write this as [Ne] 3s² 3p¹, where "[Ne]" represents the electron configuration of Neon, which is the preceding noble gas.