Question

A $s{{p}^{3}}$ hybrid orbit contains:
(A) $\dfrac{1}{4}$ s character
(B) $\dfrac{1}{2}$ s character
(C) $\dfrac{2}{3}$ s character
(D) $\dfrac{3}{4}$ s character

Answer 1

Hint: There are total four hybrid orbitals present in the$s{{p}^{3}}$ hybridization. Out of them only one orbital is obtained from s orbital. We can simply calculate the ratio of s orbitals to the total orbitals in order to find its s character.

Complete step by step answer:
Let’s first get basic information about hybridization.
- When orbitals having different energies combine in a way that all orbitals carry the same amount of energy, called hybridization. The orbital taking part in the hybridization process is called hybrid orbitals.
e.g. Orbitals of carbon atoms hybridize to form the molecule methane. Here, four orbitals, one s-orbital and three p-orbitals take part in the hybridization process. The hybrid orbitals here are oriented in a way that it can form covalent bonds with other atoms.

- There are many types of hybridization like $sp,s{{p}^{2}},s{{p}^{3}},{{d}^{2}}s{{p}^{3}}$, etc are possible in compounds. Here the alphabet suggests the symbol of hybrid orbital and the number associated with the symbol of hybrid orbital suggests the number of that type of orbitals taking part in the hybridization.
- So, now we will talk about $s{{p}^{3}}$ hybridisation. We should know that when there is combination of one ‘s’ orbital and 3 ‘p’ orbitals that belongs to the same shell of an atom and they mix together to form four new equivalent orbital, the type of hybridization is called a tetrahedral hybridization or $s{{p}^{3}}$ hybridization. The new orbitals formed are called $s{{p}^{3}}$ hybrid orbitals. We should know that in this hybridisation the hybrid orbitals are directed towards the four corners of a regular tetrahedron and make an angle of ${{109}^{\circ }}28'$ with one another.

Now, as we know that $s{{p}^{3}}$ hybridisation is made of one ‘s’ orbital and three ‘p’ orbitals, we can say that there are a total four orbitals.
So, we can calculate the s-character by following formula:
     \[\text{s-character = }\dfrac{\text{Number of s-orbitals}}{\text{Total number of hybrid orbitals}}\]

We know that the number of s-orbitals involved in $s{{p}^{3}}$ hybridization is 1 and the total number of hybrid orbital here is 4. So, we can write that
     \[\text{s-character = }\dfrac{1}{4}\]
So, the correct answer is “Option A”.

Note: Remember that while calculating the % character of an orbital in a particular hybridization, we need to find the ratio of a number of particular orbitals present to the total hybrid orbitals present. So, we can say that there will be 33% s-character in $s{{p}^{2}}$ hybridization.