Answer any FOUR of the following questions.
b. (i) Name the product formed for the reaction of isopropyl iodide on alcoholic KOH.
(ii) What is the condition to be satisfied for a compound to be chiral?

Explanation

(a) `S_N1` means unimolecular nucleophilic substitution reaction.
In this reaction rate depends only on the concentration of Alkyl halide i.e., `r prop [R-X]`
where `.r.` = rate of the reaction
`[R-X]` = Molar conc of alkyl halide
`S_N1` mechanism follows `1^(st)` order kinetics & the mechanism is of 2 steps.
Step 1 :
`underset("t - butyl bromide")(CH_3-underset(CH_3)underset(|)overset(CH_3)overset(|)(C )-Br) overset("Slow ionization")( Since this step is slow step, it is rate determined step.
Step 2 :
`CH_3-underset(CH_3)underset(|)overset(CH_3)overset(|)(C )o+ + OH^(o+) to underset("t - butyl bromide")(CH_3-underset(CH_3)underset(|)overset(CH_3)overset(|)(C )-OH)`
(b) (i) Propene
(ii) The molecule should contain asymmetric carbon atom (The C-atom is bonded to four different atoms or groups)
(c) Equimolar mixture of d- and l-isomers of an optically active compound.
Detailed Answer: 
(c) When equal amounts of two enatiomers d and l are mixed together , it gives an optically inactive form called as racemic mixture.