The electron configuration for a chlorine atom is: 1s^2 2s^2 2p^6 3s^2 3p^5. What electron configuration represents the electrons that make up only the valence electrons for a chlorine atom?

A. 1s^2
B. 1s^2 2s^2 2p^6 3s^2
C. 1s^2 2s^2 2p^6
D. 3s2 3p5

Question

The electron configuration for a chlorine atom is: 1s^2 2s^2 2p^6 3s^2 3p^5. What electron configuration represents the electrons that make up only the valence electrons for a chlorine atom?

 		A.	1s^2
 		B.	1s^2 2s^2 2p^6 3s^2
 		C.	1s^2 2s^2 2p^6
 		D.	3s2 3p5

vera_ewing · Answer

@JFraser

jfraser · Answer

how many electrons are in the $total$ electron configuration, and what makes the $valence$ level?

vera_ewing · Answer

I'm not sure...but I think the answer is D. Am I right?

jfraser · Answer

it is

vera_ewing · Answer

Ok thank you!

jfraser · Answer

chlorine has 17 electrons, and its electron configuration is:$$1s^22s^22s^632^23p^5$$valence electrons are the electrons in the $highest occupied$ level. In this case, the third level $3s^2$ and $3p^5$