What is the electron configuration of an element with atomic number 17?

1 Answer
Nov 15, 2016

The electron configuration is "1s"^2 "2s"^2 "2p"^6 "3s"^2 "3p"^51s22s22p63s23p5.

Explanation:

If the atomic number is 17, there must be 17 protons and 17 electrons.

Starting from the lowest level, we add electrons to each higher level until we have reached 17 electrons.

The electron configuration becomes "1s"^2 "2s"^2 "2p"^6 "3s"^2 "3p"^51s22s22p63s23p5.