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S9E3 - Hybridization Examples and Hybrid Orbitals

SECTION 9 - Covalent Bonding and Molecular Orbitals


If you missed my first two videos on types of hybridization and hybrid orbitals, you might want to watch them before continuing here...

All caught up?  Great, let's get started.

Today we're going to do a bunch of hybridization examples and hybrid orbital practice problems.

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The sp3 Hybridization of NH3

ex:  Completely describe the bonding in NH3
_________
answer:

➞  we first need to figure out that NH3 has 8 valence electrons.

➞  this allows us to properly draw its Lewis Structure and determine its Molecular Geometrytrigonal pyramidal.

sp3 Hybridization of NH3

Now that we have its three-dimensional geometry, we can see there's 4 effective pairs around the central nitrogen atom.

This requires sp3-hybridization for NH3

4 Effective Pairs sp3 Hybridization

Hydrogen keeps its original 1s atomic orbital. 👍

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The sp-Hybridization of N2

ex:  Completely describe the bonding in N2
_________
answer:

➞  we first need to figure out that N2 has 10 valence electrons.

➞  this allows us to properly draw its Lewis Structure and determine its Molecular Geometry linear.

N2 sp Hybridization and Hybrid Orbitals

The moleculary geometry is "linear," which has an arrangement of 2 effective pairs around each nitrogen atom.

Two effective pairs ➞ sp-hybridization for N2

Sigma and Pi Bonds of N2

As mentioned above, the N≡N triple bond contains one sigma bond (σ-bond) because there's two sp-orbitals, and two pi bonds (π-bonds) from each nitrogen's two 2p atomic orbitals.

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The Hybridization of I3-

ex:  Determine the hybridization of each iodine atom in the following anion:  I3-
_________
answer:

➞  if we can get the Lewis Structure, we can answer the question.  I3- has 22 valence electrons.

➞  this allows us to properly draw its Lewis Structure and here we go:

Hybridization of Triiodide I3- Ion

* TIP - Just count the effective pairs around each atom like this:

" s...p1...p2...p3...d1...d2 "  (sound 'em out as you count).

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Hybridization Examples

ex For each of the following molecules or ions, predict the hybridization of each atom, and completely describe the molecular structure.

a.  XeF2
b.  CO
c.  BF4-
_________
answers:

Hybridization of XeF2

a.  XeF2 has 22 valence electrons.  It's Lewis Structure is below.

The Xe has 5 effective pairs:  dsp3

Each F has 4 effective pairs:  sp3

XeF2 Hybridization

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Hybridization of CO

b.  CO is just like N2 from earlier above. 

It has 10 valence electrons, and both the carbon and the oxygen are sp-hybridized.

sp Hybridization of CO

As we saw with N2, the C≡O triple bond contains one sigma bond (σ-bond) because there's two sp-orbitals, and two pi bonds (π-bonds) from both the carbon's and the oxygen's two 2p atomic orbitals.

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Hybridization of BF4-

c.  BF4- has 32 valence electrons.  It's Lewis Structure, and it's 3-D Molecular Geometry (Shape) are shown below:

Hybridization of Tetrafluoroboron BF4- ion

From above, we see that the BF4- ion has a tetrahedral molecular geometry.

Thus boron has 4 effective pairs, which requires sp3-hybridization...

Four Effective Pairs sp3 Hybrid Orbitals

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In my next post covering SECTION 9 - Covalent Bonding and Molecular Orbitals, we'll get into the "Molecular Orbital Model."

We'll discuss Bonding and Antibonding Orbitals, Bond Order, and Molecular Orbital Diagrams.

See you there :-)