Hybridization

Hybridization in Chemistry is defined as the concept of mixing two atomic orbitals to give rise to a new type of hybridized orbitals. This intermixing usually results in the formation of hybrid orbitals having entirely different energies, shapes, etc. The atomic orbitals of the same energy level mainly take part in hybridization. However, both fully filled and half-filled orbitals can also take part in this process, provided they have equal energy.

On the other hand, we can say that the concept of hybridization is an extension of the Valence Bond Theory and it helps us to understand the formation of bonds, bond energies, and bond lengths.

Table of Contents

Key Features of Hybridization

Types of Hybridization

sp Hybridization

SP2 Hybridization

SP3 Hybridization

SP3D Hybridization

SP3D2 Hybridization

Frequently Asked Questions on Hybridization

What is Hybridization?
Hybridization is the process of combining two or more atomic orbitals with the same energy levels to form a new type of orbital with a higher energy level.

The process of hybridization involves the redistribution of the energy of orbitals of individual atoms to create orbitals of equivalent energy. This is done by combining two atomic orbitals to form a hybrid orbital in a molecule. Hybrid orbitals are usually formed by mixing two ’s’ orbitals or two ‘p’ orbitals, or an ’s’ orbital with a ‘p’ or ’d’ orbital. These hybrid orbitals are quite useful in explaining atomic bonding properties and molecular geometry.

The combination of an s orbital from the valence-shell and 3 p orbitals from the valence-shell of a carbon atom leads to the formation of 4 equivalent sp3 mixtures. These mixtures form 4 single bonds around the carbon atom, resulting in a tetrahedral arrangement with 4 different atoms.

Hybridization Video Lesson

![Hybridization]()

Also ReadThis Article

Chemical Bonding

Molecular Orbital Theory

Key Features of Hybridization

  1. Combines the advantages of two or more distinct technologies
  2. Allows for more efficient use of resources
  3. Helps users to access multiple platforms
  4. Increases compatibility and interoperability
  5. Enhances security
  6. Improves scalability and flexibility

Atomic orbitals with equal energies undergo hybridization.

The number of hybrid orbitals formed is equal to the number of atomic orbitals that are being mixed.

Even though it is not necessary for all half-filled orbitals to participate in hybridization, completely filled orbitals with slightly different energies can also take part.

Hybridization occurs only during the formation of a bond and not in an isolated gaseous atom.

If the hybridization of the molecule is known, then the shape of the molecule can be predicted.

The bigger lobe of the hybrid orbital always has a positive sign, whereas the smaller lobe on the opposite side has a negative sign.

Answer:

Question: What is the hybridization state of each of the carbon atoms in the given molecule?

H2C = CH - CN

HC ≡ C - C ≡ CH

H2C–C–C–CH2

Types of Hybridization

Let us now discuss the various types of hybridization, along with their examples, based on the types of orbitals involved in mixing. These include sp3, sp2, sp, sp3d, sp3d2, sp3d3.

SP Hybridization

sp hybridization is observed when one s and one p orbital in the same main shell of an atom mix to form two equivalent sp hybridized orbitals. These new orbitals form linear molecules with an angle of 180°.

This type of hybridization involves the mixing of one ’s’ orbital and one ‘p’ orbital of equal energy to give a new hybrid orbital known as an ‘sp’ hybridized orbital.

Diagonal hybridization is also referred to as sp hybridization.

Each sp hybridized orbital has an equal amount of s and p character - 50% s and 50% p character.

![sp Hybridization]()

Examples of sp Hybridization:

  • Methane (CH4)
  • Ammonia (NH3)
  • Water (H2O)
  • Hydrogen Fluoride (HF)

All compounds of beryllium such as BeF2, BeH2, and BeCl2 can be found here.

All compounds of carbon-containing triple bond, such as C2H2.

SP2 Hybridization

SP2 Hybridization is observed when one s and two p orbitals of the same shell of an atom mix to form three equivalent orbitals, known as SP2 Hybrid Orbitals.

Trigonal hybridization is also known as sp2 hybridization.

It involves mixing of one ’s’ orbital and two ‘p’ orbitals of equal energy to give a new hybrid orbital known as sp2.

A mixture of s and p orbitals form a trigonal symmetry and is maintained at 1200.

All three hybrid orbitals remain in one plane and form an angle of 120° with each other. Each of the hybrid orbitals has a 33.33% ’s’ character and 66.66% ‘p’ character.

Molecules with a central atom linked to three atoms and having sp2 hybridization have a triangular planar shape.

![sp2 Hybridization]()

Examples of sp2 Hybridization

All the compounds of Boron:

  • BF3
  • BH3

Ethylene (C2H4) is one of the compounds of carbon containing a carbon-carbon double bond.

SP3 Hybridization

When one ’s’ orbital and three ‘p’ orbitals belonging to the same shell of an atom mix together to form four new equivalent orbitals, the type of hybridization is called Tetrahedral Hybridization or sp3. The new orbitals formed are called sp3 Hybrid Orbitals.

These are directed towards the four corners of a regular tetrahedron and form an angle of 109°28’ with each other.

The angle between the sp3 hybrid orbitals is 109.280°

Each sp$^3$ hybrid orbital has 25% s character and 75% p character.

Example of sp3 hybridization: Ethane (C2H6), as well as Methane.

sp3 Hybridization

SP3D Hybridization

The mixing of 1s, 3p, and 1d orbitals to form 5 sp3d hybridized orbitals of equal energy results in a trigonal bipyramidal geometry.

The combination of the s, p, and d orbitals creates a trigonal bipyramidal symmetry.

Three hybrid orbitals lie in the horizontal plane, inclined at an angle of 120° to each other, known as the equatorial orbitals.

The remaining two orbitals lie in the vertical plane at 90 degrees to the plane of the equatorial orbitals, known as axial orbitals.

Example: Hybridization in Phosphorus Pentachloride (PCl5)

![sp3d Hybridization]()

SP3d2 Hybridization

The intermixing of 1s, 3p, and 2d orbitals in sp3d2 hybridization results in the formation of 6 identical sp3d2hybrid orbitals.

These 6 orbitals are directed towards the vertices of an octahedron.

They are inclined at an angle of 90° to one another.

sp3d2-Hybridization

Frequently Asked Questions on Hybridization

What are the Types of Hybridization?

The hybridization of the mixing orbitals can be classified as:

Sp Hybridization (Beryllium Chloride, Acetylene)

Sp\2 Hybridization (Boron Trichloride, Ethylene)

sp3 Hybridization (Methane, Ethane)

SP3d Hybridization (Phosphorus Pentachloride)

SP3d2 Hybridization (Sulfur Hexafluoride)

SP3d3 Hybridization (Iodine Heptafluoride)

Learn more about VSEPR theory, its postulates, and limitations

Which hybrid orbital among sp, sp2, and sp3 is more electronegative?

The percentage of s character in sp, sp2, and sp3 hybridized carbon is 50%, 33.33%, and 25%, respectively.

Also Read:

Hydrogen Bonding

Covalent Bond

The sp hybridized carbon is more electronegative than sp2 and sp3 due to its increased s-character, which allows it to be more closely attracted to the nucleus and thus more electronegative. This is because the spherical shape of the s orbital allows it to be attracted evenly by the nucleus from all directions.

What are the Benefits of Hybridization over Parent Atoms?

The advantages of hybrid orbitals over their parent orbitals:

Parents: Because it is directional, unlike the s orbital.

P orbital: Because it has higher energy than the parent p orbital.

What are Hybrid Orbitals?

The hybrid orbitals can be defined as the combination of standard atomic orbitals, resulting in the formation of new atomic orbitals.

⇒ Check: Fajan’s Rule and its Postulates

The hybrid orbitals formed during hybridization possess a different geometry and energy compared to the standard atomic orbitals. Additionally, the overlap of the orbitals minimizes the energy of the molecule, resulting in degenerate hybrid orbitals.

1s and 1p: sp orbitals

1s and 2p: sp^2 Orbitals

1s and 3p: sp3 orbitals

1s, 3p, and 1d: **sp3d** orbitals

1s, 3p, and 2d: sp3d2 orbitals

What is the Difference Between sp, sp2, and sp3 Hybridization?

SP Hybridization occurs due to the mixing of one S and one P atomic orbital. SP2 Hybridization is the mixing of one S and two P atomic orbitals. SP3 Hybridization is the mixing of one S and three P atomic orbitals.

What is the percentage of s and p character in s, p, sp2, and sp3 hybrid orbitals?

The percentage of s and p character in sp, sp2 and sp3 hybrid orbitals are:

  • sp Hybrid Orbital: 50% s character and 50% p character
  • sp2 Hybrid Orbital: 33% s character and 67% p character
  • sp3 Hybrid Orbital: 25% s character and 75% p character

S’s characteristic is 50%, and P’s characteristic is 50%.

Sp2: Characteristic 33.33% | P Characteristic 66.66%

Sp3: Characteristic 25% and P characteristic 75%.

The five basic shapes of Hybridization are:

  1. sp³ Hybridization - occurs when the s orbital and three p orbitals combine to form four equivalent sp³ hybrid orbitals
  2. sp² Hybridization - occurs when the s orbital and two p orbitals combine to form three equivalent sp² hybrid orbitals
  3. sp Hybridization - occurs when the s orbital and one p orbital combine to form two equivalent sp hybrid orbitals
  4. spd Hybridization - occurs when the s orbital, two p orbitals, and one d orbital combine to form four equivalent spd hybrid orbitals
  5. spdf Hybridization - occurs when the s orbital, three p orbitals, and one d orbital combine to form five equivalent spdf hybrid orbitals

The five basic shapes of hybridization are:

  1. Linear
  2. Trigonal Planar
  3. Tetrahedral
  4. Trigonal Bipyramidal
  5. Octahedral

The Geometry of the Orbital Arrangement:

Linear: Two electron groups are involved resulting in sp hybridization, with an angle of 180° between the orbitals.

Trigonal Planar: Involves three electron groups resulting in sp2 hybridization, with an angle of 120° between the orbitals.

Tetrahedral: Four electron groups are involved, resulting in sp3 hybridization, with an angle of 109.5° between the orbitals.

Trigonal Bipyramidal: Involving five electron groups, the resulting hybridization is sp3d, with the angle between the orbitals being 90° and 120°.

Octahedral: Six electron groups are involved, resulting in sp3d2 hybridization, with an angle of 90° between the orbitals.

SP3 Hybridization in Methane

SP3 hybridization in methane occurs when the carbon atom in the molecule forms four bonds with the four hydrogen atoms. This forms a tetrahedral structure, which is the result of the carbon atom hybridizing its 2s and 2p orbitals into four sp3 orbitals. The four sp3 orbitals created are oriented in a tetrahedral shape, with bond angles of 109.5°. Each of the sp3 orbitals contain one bonding pair of electrons, resulting in the four single covalent bonds between the carbon and hydrogen atoms.

The 2s and all the three (3p) orbitals of carbon hybridize to form four sp3 orbitals. These hybrid orbitals bond with four atoms of hydrogen through sp3-s orbital overlap resulting in CH4 (methane). The geometry of orbital arrangement due to the minimum electron repulsion is tetrahedral.

Why does an amide molecule look sp3 hybridized, but is actually sp2 hybridized?

The general process of hybridization will change if the atom has either two or more p orbitals surrounding it, or a lone pair that can jump into a p orbital. Therefore, in the case of an amide molecule, the lone pair will enter a p orbital to form three adjacent, parallel p orbitals (conjugation).

What are the results of sp, sp2, and sp3 Hybridization?

In sp and sp2 hybridization, there are two and one unhybridized p orbitals respectively, whereas in sp3 hybridization, there are no unhybridized p orbitals.

Molecular orbitals are formed when two atomic orbitals overlap and hybrid orbitals are formed when atomic orbitals mix together to form a new type of orbital.

The interactions between the atomic orbitals of two different atoms result in molecular orbitals, whereas when the atomic orbitals of the same atom interact they form hybrid orbitals.