How are the electrons and argon arranged?

Electrons in an argon atom are arranged in energy levels or shells around the nucleus. Argon has a total of 18 electrons, with 2 in the first shell and 8 in the second shell, filling it completely, and 8 in the third shell, which also fills it according to the octet rule. This arrangement gives argon its characteristic stability and makes it a noble gas, meaning it is largely unreactive. The electron configuration of argon is 1s² 2s² 2p⁶ 3s² 3p⁶.