Glycerol $\xrightarrow{KHSO_4} A$ $\xrightarrow{LiAlH_4} B$
$A$ and $B$ are :

What is the number of hydroxyl groups present in propylene glycol?

$CH_3 CH_2 OH \underset{\text{step-}1}{\stackrel{Cl_2}{\longrightarrow}} CH_3 CHO$ $\underset{\text{step-}2}{\stackrel{3 Cl_2}{\longrightarrow}} Cl_3 CCHO$
In the above reactions,the role of $Cl_2$ in step-$1$ and step-$2$ respectively is:

An organic compound $(A)$ reacts with sodium metal to form $(B)$. When $(A)$ is heated with concentrated $H_2SO_4$,it produces diethyl ether. What are $(A)$ and $(B)$ respectively?

What are $X$ and $Y$ in the following reactions?

In the given pairs of alcohols,in which pair is the second alcohol more reactive than the first towards hydrogen bromide $(HBr)$?