Hydrogen Cyanide is a chemical compound with the chemical formula of HCN. It is also known as prussic acid and is an extremely poisonous liquid. Hydrogen Cyanide is colorless and is used in the industrial production of several compounds.
In this blog post, we are going to look at its hybridization that can help us understand its chemical and physical properties. To know the hybridization of any molecule, we first need to look at its Lewis Structure.
Hybridization of HCN
Hydrogen Cyanide is made up of three atoms: Hydrogen, Carbon, and Nitrogen. Carbon has a single bond with a Hydrogen atom and a triple bond with a Nitrogen atom.
Here the Hydrogen atom only needs one valence electron to attain a stable structure. Hence, there is no hybridization for a Hydrogen atom as it is sharing one electron with a Carbon atom. The electron in its 1s orbital is shared with the Carbon atom.
The carbon atom, which is also the central atom, is the one that requires hybridized orbitals to accommodate the shared electrons. We can find out the hybridization of the atom by using some simple and quick methods such as Steric Number and Number of sigma bonds.
Finding out Steric Number for the molecule
One can use several ways to find out the hybridization of an atom, one of them being finding the steric number for the atom.
Steric number = number of atoms attached to the central atom + number of lone pairs
There are no lone pairs of electrons on the Carbon atom, but it forms bonds with two atoms here: Nitrogen and Hydrogen.
Thus Steric Number of Carbon – 2+0
= 2
As the steric number is 2, referring to the table stated below, we can say that it is sp hybridized.
Generally, molecules with linear molecular geometry have sp hybridization as the central atom forms bonds with two atoms only.
Number of sigma bonds in the molecule
Another way to find out the hybridization of the molecule is to look at the number of sigma bonds formed. In HCN, there are two sigma bonds, C-H and C-N. The number of sigma bonds is equal to the number of hybrid orbitals formed. So the hybridization for HCN molecule is sp hybridization.
Concluding Remarks
We can say that HCN, Hydrogen Cyanide, is a linear molecule with sp hybridization to conclude this blog post. The bond angles are 180°and two hybrid orbitals are formed for two sigma bonds formed in this molecule.