The noble gas electron configuration for potassium (K) is:

[Ar] 4s¹

Here's how to understand it:

* [Ar] represents the electron configuration of the noble gas Argon (1s²2s²2p⁶3s²3p⁶), which is the closest noble gas to potassium in the periodic table.

* 4s¹ indicates that potassium has one electron in its 4s orbital.

This configuration means that potassium has the same electron arrangement as Argon, but with one additional electron in the 4s orbital. This extra electron is what makes potassium reactive and gives it its characteristic properties.