$2-$chloropentane on halogenation with chlorine gives $2,3-$dichloropentane. What will be the structure of the free radical species formed in the reaction?

Consider the following compound $(X)$:
$H-C \equiv C-CH_2-CH(CH_3)-CH_3$
The most stable and least stable carbon radicals,respectively,produced by homolytic cleavage of the corresponding $C-H$ bond are:

Which of the following is the electrophile involved in the given reaction?

Given below are two statements:
Statement $I$: $(CH_3)_3C^{+}$ is more stable than $CH_3^{+}$ as nine hyperconjugation interactions are possible in $(CH_3)_3C^{+}$.
Statement $II$: $CH_3^{+}$ is less stable than $(CH_3)_3C^{+}$ as only three hyperconjugation interactions are possible in $CH_3^{+}$.
In the light of the above statements,choose the correct answer from the options given below.

Arrange the following carbocations in decreasing order of stability.

Based upon an understanding of product stability,predict the product formed when the following dianion reacts with one equivalent of acid $(H^+)$.