Acrolein is formed when glycerol is heated with -

Which of the following structures corresponds to the product expected when an excess of $C_6H_6$ reacts with $CH_2Cl_2$ in the presence of anhydrous $AlCl_3$?

Arrange benzene,$n$-hexane and ethyne in decreasing order of their acidic behaviour.

Identify $A$ in the following reaction sequence:

The cycloalkane $(X)$ on bromination consumes one mole of bromine per mole of $(X)$ and gives product $(Y)$ in which $C:Br$ ratio is $3:1$. The percentage of bromine in the product $(Y)$ is $ . . . . . . \%$ (Nearest integer).
(Given: Molar mass in $g \ mol^{-1}$, $H:1, C:12, O:16, Br:80$)

Identify the reaction that does not produce an alkene.