Write any two differences between $\displaystyle \mathrm{S}_{\mathrm{N}} 1$ and $\displaystyle \mathrm{S}_{\mathrm{N}} 2$ reactions. Which of the following compounds would undergo $\displaystyle \mathrm{S}_{\mathrm{N}} 1$ reaction faster and why? or

SN1 SN2 Unimolecular Bimolecular It follows first order kinetics It follows second order kinetics Retention of configuration Inversion of configuration Racemisation occurs No racemisation is seen Takes place through formation of carbocation Takes place through formation of transition state Occurs in polar protic solvent Occurs in polar aprotic solvent Rate is independent of the concentration of the nucleophile. Rate is dependent on the concentration of the nucleophile., because of the stability of benzyl carbocation