S_N1 reaction of alkyl halides lead to;

Racemisation

The answer to the question "\(S_N1\) reaction of alkyl halides lead to" is (3) racemization.

The \(S_N1\) reaction is a two-step process that involves the formation of a carbocation intermediate. The carbocation intermediate is a planar molecule, so the nucleophile can attack from either side of the plane. This means that the configuration of the product is inverted relative to the starting material. However, if the starting material is a racemic mixture, the product will also be a racemic mixture. This is because the SN1 reaction can proceed through either of two enantiomeric carbocation intermediates. The nucleophile can attack from either side of either carbocation intermediate, so the product will be a racemic mixture.