Difference Between sp, sp2, and sp3 Hybridisation

In a nutshell, this is a process in which two types of orbitals (i.e., s and p) of a common atom are combined to form entirely new orbitals of equal energies in a shell. The new orbitals are referred to as hybrid orbits, though it is called hybridisation.

After hybridisation, the atom changes its physical and chemical properties to a certain extent. Moreover, this concept originated from the valence bond theory. The hybridisation of any atom can result in different hybrid forms, namely, sp, sp², sp³, sp³d, and sp³d². We will discuss the difference between the sp, sp², and sp³ hybridisation. Let’s directly dive into the topic.

Difference Between sp, sp², and sp³ Hybridisation: Overview

The key reason behind the variance in the sp,sp², and sp³ hybridised atoms lies in the ratios of their orbital characteristics. In simpler words, particles have two types of orbitals in general. They are ‘s’ and ‘p.’ Both of them carry different kinds of characteristics. Though when they combine:

• Sp hybridisation occurs if both orbitals elements are proportionate (50%)

• If s orbitals characteristics are 1/3^rd of atom (33%), sp² hybridisation takes place

• If s orbitals characteristics are 1/4^th of atom (25%), sp³ hybridisation takes place

Furthermore, hybridisation only takes place between the orbitals of the same energy. However, orbitals of the same energy can combine regardless of whether they are complete or not.

sp Hybridisation 

sp is the primary form of sp hybridisation. As said, sp hybridisation occurs when an s orbital is combined with one p orbital proportionately. This hybridisation is also referred to as diagonal hybridization. 

• Characteristics

In sp hybridisation, the angle between the s and p orbitals is linear or 180 degrees. Moreover, any atom-shell comprises three p orbitals. And, after the hybridisation, only one p orbital is hybridised here. However, two p orbitals are left unhybridised. 

• Examples

Beryllium Chloride (BeCl₂)

Acetylene (C₂H₂)

sp² Hybridisation

sp² hybridisation is one next step of sp hybridisation. Unlike sp hybridisation, a shell does not comprise one p orbital against one s orbital. In sp² hybridisation, one orbital bond with two p orbitals forms three new orbitals, referred to as sp² hybridised orbitals. This is where the difference is reflected. As a result, an atom gets more characteristics of p orbitals (2/3^rd) after hybridisation.  

• Characteristics

As two p orbitals bond with s orbital, only one p orbital is left not hybridised. There are overall three orbitals in this hybridisation, though its arrangement is in the trigonal planar shape. The angle among these orbitals is 120 degrees, decreasing the congestion among all three orbitals. The atom comprises 33% s characteristics. 

• Examples

Boron trichloride (BCl₃)

Ethylene (C₂H₄)

sp³ Hybridisation

sp³ is another type of hybridisation in which one orbital overlaps with all three present orbitals of p. As a result, four new orbitals of equal energy are formed in a shell. These are often referred to as sp³ hybridised orbitals. And the atom is termed as sp³ hybridised atom. As p orbitals are the majority orbitals in a shell, the atom contains more characteristics of p orbitals. This hybridisation is also termed tetrahedral hybridisation.

• Characteristics

All p orbitals are overlapped here, though all orbitals are hybridised. Since there is only one s orbital from the four orbitals of an atom, and the sp³ hybridised atoms have only 25% s characteristics, the arrangement of these orbitals is in tetrahedral, with each orbital placed at 109.5 degrees. 

• Examples

Methane (CH₄)

Ethane (C₂H)

Ammonia (NH₃)

A water molecule (H₂O)

Difference Between sp, sp², and sp³

Also See:

• Difference Between Zener Breakdown and Avalanche Breakdown
• Difference between Voltage and Current in Detail
• Difference Between Fractions and Rational Numbers
• Difference between Cell and Battery
• Difference Between Circuit Switching and Packet Switching
• Difference between Baking Soda And Baking Powder

Conclusion

From all the above, we have learned that hybridisation is a process in which one s and p (one or more than one) orbitals of one shell combine with each other and form new orbitals. The hybridisation of an atom takes place in three primary types.=: sp, sp², and sp³. All hybridisations differ by their orbital characteristics. Sp hybridised atoms have 50% s characteristics and 50 p characteristics. Further, sp² hybridised atoms have 33% s and 66% p characteristics. Lastly, sp three hybridised atoms have 25% s and 75% p characteristics.