Question

Bond length of which of the following types of bonds is maximum?

1. $s{p^2} - s{p^2}$
2. $sp - sp$
3. $s{p^3} - s{p^3}$
4. $s{p^3} - s{p^2}$

Answer 1

Bond length also known as bond distance in molecular geometry represents the average distance of the nuclei of two bonded atoms forming a molecule. To determine length of the bond between the atoms the number of electrons are considered that is through bond order. Stronger will be the pull between two atoms if there is high bond order and the bond will be shorter.

Complete step by step answer:
$s{p^3}$ hybridization explains about the tetrahedral structure of molecules. In this, the $2s$ and $2p$ orbitals hybridize to form four $sp$ orbitals, having 75% of $p$ character and 25% of $s$ character. In this structure, electron repulsion is minimized.
$s{p^2}\;$ hybridization explain about the trigonal planar structure of molecules In this, the $2s$ and $2p$ orbitals hybridize to form three $sp$ orbitals, having 67% of $p$ and 33% of $s$ character. The frontal lobes align themselves in the trigonal planar structure.
$sp$hybridization explains about the linear structure in molecules. In this, the $2s$ and $2p$ orbitals hybridize to form two $sp$ orbitals, having 50% of $s$ and 50% of $p$ character. The frontal lobes face away from each other and form a straight line having a 180° angle between the two orbitals.
The average lengths of the single bonds are given below.
$s{p^3} - s{p^3}$= 154 pm
$s{p^3} - s{p^2}$= 150 pm
$s{p^2} - s{p^2}$= 146 pm
$sp - sp$= 138 pm
Therefore the bond length of $s{p^3} - s{p^3}$ is maximum.

So, the correct answer is Option C.

Note: With the calculation of the bond length between the atoms the knowledge about the bond energy can be generated. If the bond length is shorter, the bond energy will be high due to high force of attraction and the energy will be low if the bond length is quite big.