Question

The total number of \[\sigma \] and \[\pi \] bonds present in azobenzene are:
A.24 \[\sigma \] , 6 \[\pi \]
B.25 \[\sigma \], 7 \[\pi \]
C.28 \[\sigma \], 6 \[\pi \]
D.27 \[\sigma \], 6 \[\pi \]

Answer 1

Hint: To obtain the solution of this question, we must first understand the concept of \[\sigma \] bonds and \[\pi \] bonds. Then we must draw the molecular structure of azobenzene and then individually count \[\sigma \] bonds and \[\pi \] bonds.

Complete step by step answer:
Before proceeding with the solution of this question, let us understand some basic concepts and terms:
 \[\sigma \] and \[\pi \] bonds are both covalent in nature
 \[\sigma \] bonds are formed when there is end to end overlapping of orbitals. It can also be represented as a single bond
 \[\pi \] bonds are formed when there is overlapping of a lobe of one atomic orbital. It can also be represented as a double bond.
The bond strength of \[\sigma \] bonds is stronger than \[\pi \] bonds
The structure of Azobenzene can be given by:

From this structure, we can observe that the number of single and double bonds are:
Number of single bonds = 25 = number of \[\sigma \] bonds
Number of double bonds = 7 = number of \[\pi \] bonds
Hence, there are 25 \[\sigma \] bonds and 7 \[\pi \] bonds

Hence, Option B is the correct option.

Note:
Azobenzene is a molecule whose structure comprises two phenyl rings linked by a N=N double bond; the parent compound of the azobenzene class of compounds. One of the largest applications of the compound azobenzene takes place in the colouring and dye industry.