The reaction of one mole of $3-$chlorohexane with one mole of $NaI$ in the presence of acetone yields which of the following as the major product?

Heating methyl chloride with zinc in a closed tube produces...............

Which alkyl halide from the following pairs would you expect to react more rapidly by an $S_N2$ mechanism? Explain your answer.
$(i)$ $CH_3CH_2CH_2CH_2Br$ or $CH_3CH_2CH(Br)CH_3$
$(ii)$ $CH_3CH_2CH(Br)CH_3$ or $(CH_3)_3CBr$
$(iii)$ $CH_3CH(CH_3)CH_2CH_2Br$ or $CH_3CH_2CH(CH_3)CH_2Br$

Given below are two statements:
Statement $(I)$: Benzyl chloride reacts faster in $S_N1$ mechanism than ethyl chloride.
Statement $(II)$: Ethyl carbocation intermediate is less stabilized by hyperconjugation than benzyl carbocation by resonance.
In the light of the above statements, choose the correct answer from the options given below:

Which among the following is $NOT$ a feature of $S_{N}2$ mechanism?

Which of the following is likely to undergo racemization during alkaline hydrolysis by $SN^1$ mechanism?