Unpaired electrons

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

Jessa Maheras 4F
Posts: 121
Joined: Fri Aug 02, 2019 12:16 am

Unpaired electrons

Does each unpaired electron in a hybridized orbital represent a potential bond the atom can form? Why?

Justin Vayakone 1C
Posts: 110
Joined: Sat Sep 07, 2019 12:19 am

Re: Unpaired electrons

Yes each hybridized orbital represents bonds in the molecule. Let's take methane (CH4) for example. Because there are four regions of electron density around the Carbon atom, the s and p orbitals combine to create sp^3 orbitals: https://ibb.co/DGWMx8v
Each of these sp^3 orbitals has an unpaired electron that will pair with an electron with each of the four H electrons to form the four covalent bonds of the molecule.

Here's another example, C2H4 (ethylene). Each carbon has three regions of electron density, so sp^2 orbitals are used: https://ibb.co/7G0zDNP
The sp^2 orbitals take care of all of the sigma bonds in ethylene while the remaining 2p orbital is used for the pi bond between the two Carbon atoms.

Chris Tai 1B
Posts: 102
Joined: Sat Aug 24, 2019 12:16 am

Re: Unpaired electrons

The reason there must be some hybridization in the orbitals is that it best fits the VSEPR model. If the valence electrons were only that of the p orbitals attached to carbon, then in the methane example the hydrogens would be attached to carbon at 90 degree angles from each other, which clearly violates the empirically tested and observed model of 109.5 degrees. Thus, there must be 4 hybridized sp^3 orbitals to satisfy such observation.