Most reactive for $S_{N}1$ reaction is

$(+)-2-$chloro$-2-$phenylethane in toluene racemises slowly in the presence of small amount of $SbCl_5$, due to the formation of

The major product of the following reaction is:

$2-$Bromobutane on heating with alcoholic $KOH$ forms

$ . . . . . . $ compound is slowly oxidized by air in the presence of light to an extremely poisonous gas, carbonyl chloride.

Predict the product of the following reaction:
(Image: $A$ chiral carbon attached to a phenyl ring with a para-chloro group,a deuterium atom $(D)$,a hydrogen atom $(H)$,and a chlorine atom (Cl) in a specific stereochemical configuration. The reaction is with $NaI$ in acetone.)