If the electron configuration of an element is 1S²2S²2P⁵…
If the electron configuration of an element is 1S²2S²2P⁵, how many unpaired electrons are there?
According to Hund’s rule, electrons must first of all fill up sub-orbitals singly, before pairing up.
There is just one sub-orbital for S – orbital, and 3 sub-orbitals for P – orbital.
The 1S and 2S orbitals are completely filled, but the 2P orbital which has 5 electrons and 3 sub-orbitals to share them, will firstly be fill with single electrons, and then the two remaining electrons will pair up two sub-orbitals, leaving behind one unpaired electron.
1S[↑↓] 2S[↑↓] 2P[↑↓][↑↓][↑]
Now for the right answer to the above question:
- Option A is incorrect.
- Option B is incorrect.
- C is correct.
- D is not the correct answer.
You may please note these/this:
- Hund’s rules states that electrons must singly fill up sub-orbitals before pairing up.
If you love our answers, you can login to comment and say hi to us at the comment section…
To raise new related questions, click the ASK A QUESTION BOTTON down this page!
/ culled from 2015 JAMB-UTME Chemistry PAST question 30 /
If the electron configuration of an element is 1S²2S²2P⁵... » QuizTablet
Course Provider: Organization
Course Provider Name: N.D Sammy
Course Provider URL: QuizTablet.com