Question

The number of $s{p^2}$ hybridized carbon in benzyne is
(1).4
(2).6
(3).5
(4).3

Answer 1

We have to know that benzyne is one of the derivatives of benzene. The major difference between benzene and benzyne is that benzene contains alternate single and double bonds whereas in benzyne, a triple bond would also be found.

Complete answer:
From the name benzyne, we can predict that compound benzyne comes under aryne. We have to know that the triple bond present in the structure of benzyne is not a normal triple bond because the second pi bond leads to weak interaction of $s{p^2}$ hybrid orbitals that are found in planar rings. The triple bond is not linear because of the constraint of a six membered ring of benzyne. Let us take that two triple bonded atoms of carbon in benzyne which are sp hybridized similar to typical triple bonded atoms of carbons, then there will be more strain in the angle of the molecule that leads to instability whereas this molecule is not stable. So, each triple bonded atom of carbon is $s{p^2}$ hybridized, but in this case, the two carbons that are $s{p^2}$ hybridized orbitals are not parallel to one other goes through lateral overlap to give rise to pi bond which is not portion of cloud of pi electron that lies down and up of the planar benzene ring. So, all atoms of carbon in benzene are $s{p^2}$ hybridized.
We can say that the number of $s{p^2}$ hybridized carbon in benzyne is six.

Option (2) is correct.

Note:
We have to know that the structure exhibits the presence of one sigma bond and two pi bond that results in assumption that atoms of carbon which forms the bond are sp hybrid whereas these atoms of carbon are $s{p^2}$ due to the reasons which we mentioned above.