Homework 4.43

$sp, sp^{2}, sp^{3}, dsp^{3}, d^{2}sp^{3}$

Taravat_Lakzian_1C
Posts: 18
Joined: Wed Sep 21, 2016 2:56 pm

Homework 4.43

For question 43, it gives you that the bond angle of the sp^3 hybridized atom is 109.5 degrees and the bond angle of an sp^2 hybridized atom is 120 degrees.
The question asks if you expect the bond angle between two hybrid orbitals to increase or decrease as the s-character of the hybrids is increased? I know that the answer from the back of the books says that as the s-characters increase, the bond angle between two hybrid orbitals increases. Could someone please explain why, thank you.

Xinyi_Yan_3L
Posts: 21
Joined: Wed Sep 21, 2016 2:56 pm

Re: Homework 4.43

I don't know the exact reason, but we can make generalization by comparing sp3 and sp2 orbitals. The sp2 orbitals has less p-character and more s-character than sp3 (you may think of sp2 has 1/3 s, while sp3 has 1/4 s), and has lager bond angles.
Generally, the more s-character the hybrid orbital has, the more bonds the molecules has. Thus the bond angles are decreasing.