Mustard gas is obtained by

$cis-3-hexene \xrightarrow{(a)} \text{meso } 3,4-hexanediol$
$trans-3-hexene \xrightarrow{(b)} \text{meso } 3,4-hexanediol$
Choose the pair of reagents $(a, b)$ for the above conversions.

What product is formed when $Br_2$ is added to ethylene in the presence of aqueous $NaCl$?

Which of the following can be used as the test for unsaturation with regard to colour change of reaction?

In the reaction $CH_2=CH_2$ $\xrightarrow{HOCl} M$ $\xrightarrow{R} HO-CH_2-CH_2-OH$,where $M$ is a molecule and $R$ is a reagent,$M$ and $R$ are:

The number of hydrogen atoms which can participate in hyperconjugation in $Y$ is
$CH_3CH_2COCH_3$ $\xrightarrow{LiAlH_4} X$ $\xrightarrow{conc. H_2SO_4, \Delta} Y \text{ (Major)}$