Orbital Hybridisation

Question 1

What is orbital Hybridisation?

Answer 1

• Hybridisation means “mixing” and so orbital hybridisation literally means “orbital mixing”.

Question 2

What events take place during sp3 hybridisation?

Answer 2

-An electron is first promoted from the filled 2s sub-shell to the empty 2p orbital.

-The one 2s orbital and three 2p orbitals then mix (hybridise) to form four, equal energy sp3 hybrid orbitals.

-The four sp3 hybrid orbital’s adopt a tetrahedral conformation around the carbon atom.

-This allows the orbital’s to be as far away as possible from each other to minimise repulsive interactions.

-The angle between each hybrid orbital is 109.5o.

-Remember to always think in 3-D. In 2 dimensions the maximum bond angle between 4 hybrid orbitals would be 90o.

Question 3

If carbon forms 4 sigma bonds, what shape does the molecule form?

Answer 3

the shape about the carbon atom will be tetrahedral.

Question 4

name two examples of molecules that undergo sp3 hybridisation?

Answer 4

-Ammonia
-Water

Question 5

What is sp2 hybridisation?

Answer 5

→ One 2s orbital and two 2p orbitals hybridise to form three, equivalent sp2 hybrid orbitals.

→ This leaves one unused p orbital with an electron in it.

→ The three sp2 hybrid orbital’s all lie in the same plane, at 120° to each other. The shape is trigonal planar.

→ The remaining p orbital lies perpendicular to the plane of the sp2 hybrid orbital’s.

Question 6

what is SP hydrisation?

Answer 6

where one 2s orbital and one 2p orbital mix to form two equivalent sp hybrid orbitals.

Question 7

what is SP3D hybridisation?

Answer 7

One 3s, three 3p and one 3d orbital combine to form 5 sp3d hybrid orbitals.

Question 8

what examples of molecules is SP3D Hybridisation found?

Answer 8

-PCl5
-SF6

Question 9

If there are 2 BP and 0 LP what kind of Hybridisation is formed and what shapes are produced?

Answer 9

-SP Hybridisation
-Electronic geometry (linear)
-Molecular geometry (linear)

Question 10

If there are 3 BP and 1 LP what kind of Hybridisation is formed and what shapes are produced?

Answer 10

-SP3 Hybridisation
-Electronic geometry (Trigonal Planar)
-Molecular geometry (pyramidal)

Question 10

If there are 3 BP and 0 LP what kind of Hybridisation is formed and what shapes are produced?

Answer 10

-SP2 Hybridisation
-Electronic geometry (Trigonal Planar)
-Molecular geometry (Trigonal Planar)

Question 11

If there are 4 BP and 0 LP what kind of Hybridisation is formed and what shapes are produced?

Answer 11

-SP3 Hybridisation
-Electronic geometry (Trigonal Planar)
-Molecular geometry (Trigonal planar)

Question 12

If there are 2 BP and 2 LP what kind of Hybridisation is formed and what shapes are produced?

Answer 12

-SP3 Hybridisation
-Electronic geometry (Trigonal Planar)
-Molecular geometry (bent/angular)

Question 13

If there are 5 BP and 0 LP what kind of Hybridisation is formed and what shapes are produced?

Answer 13

-SP3D Hybridisation
-Electronic geometry (Trigonal bipyramidal)
-Molecular geometry (Trigonal bipyramidal)

Question 14

If there are 6 BP and 0 LP what kind of Hybridisation is formed and what shapes are produced?

Answer 14

-SP3D2 Hybridisation
-Electronic geometry (Octahedral)
-Molecular geometry (Octahedral)