Consider the following reaction
ethanol `overset(PBr_(3))(rarr)Xoverset(alc.KOH)(rarr)Yoverset((i)H_(2)SO_(4),"room temp".)underset((ii)H_(2)O,heat)(rarr)Z` the product `Z` is

Options

A. `CH_(3)CH_(2)OCH_(2)CH_(3)`
B. `CH_(3)CH_(2)OSO_(3)H`
C. `CH_(3)CH_(2)OH`
D. `CH_(2)=CH_(2)`

Answer

C

Explanation

`CH_(3)CH_(2)OH overset(PBr_(3))rarr underset((X))(CH_(3)CH_(2)Br) overset(alc.KOH)underset(-HBr)rarr underset((Y))(CH_(2)=CH_(3))`
`underset(temp)overset(H_(@)SO_(4)"room")rarr underset("ethyl hydrogen sulphate")(CH_(3)CH_(2)OSO_(2)OH) overset(H_(2)O)underset(heat)rarr underset((Z))(CH_(3)CH_(2)OH)`
`PBr_(3)` causes replacement of `OH` by `Br` to yield bromide. Alcoholic `KOH` causes dehydrobromination to yield alkene which adds on on sulphuric acid to prodluce ethyl hydrogen sulphate. On heating with `H_(2)O`, it undergoes hydrolysis to yield ethanol.