Which electron configuration represents the electrons in an atom of chlorine in an excited state?
(1) 2-7-7 (3) 2-8-7
(2) 2-7-8 (4) 2-8-8



Answer :

Answer;

(4) 2-8-8

Explanation;

An electron configuration shows the arrangement of electrons around the nucleus of an atom. At the ground state (the most stable state for electrons) the electron configuration of chlorine is 2-8-7. Chlorine is a halogen that contains 17 electrons, to attain a stable configuration chlorine requires to gain 1 electron.

-At the excited state chlorine will therefore have an electron configuration of 2-8-8.