Benzene reacts with chlorine to form benzene hexachloride in the presence of:

The reaction of toluene with chlorine in the presence of light gives

For isomeric hydrocarbons with molecular formula $C_9H_{12}$ that give a negative Baeyer's test,determine the total number of isomers that possess four different non-aliphatic substitution sites.

The number of $sp^2-s$ sigma bonds in benzene are

The correct order of reactivity towards electrophilic substitution reaction is:

For the given reaction:
$CH_{3}-CH=CHBr \xrightarrow[2. \text{Red hot iron tube}, 873 \text{ K}]{1. \text{NaNH}_{2}} A$ (major product)
Identify the major product $A$.