$A$ solution of $D(+)-1-$chloro$-1-$phenylethane in toluene racemises slowly in the presence of a small amount of $SbCl_5$,due to the formation of:

The major product obtained in the following reaction is $C_2H_5ONa + (CH_3)_3C-Cl \rightarrow$

$Cl-CH_2-C(CH_3)_2-CH_2-CH_2-Cl + I^- \xrightarrow[DMF]{} \text{product}$; The major product of this reaction is:

$50\%$ of the reagent is used for dehydrohalogenation of $6.45 \ g$ $CH_3CH_2Cl$. What will be the weight of the main product obtained (in $g$)? [At. mass of $H$,$C$,and $Cl$ are $1$,$12$,and $35.5 \ g \ mol^{-1}$ respectively]

Which one of the following has the highest boiling point?

The compound $A$ (major product) is