Answer the following questions :
(i) What is meant by chirality of a compound? Give an example.
(ii)Which one of the following compounds is more easily hydrolyzed by KOH and why?
CH₃CHClCH₂CH₃ or CH₃CH₂CH₂Cl

(iii) Which one undergoes S_N2substitution reaction faster and why?

(i) Compounds which form mirror images and are non-superimposable to each other (existing as enantiomers) are known as chiral compounds. So, chirality is the property of a molecule to have non-superimposable mirror image. These molecules contain one asymmetric carbon atom. They do not have a plane of symmetry. Similarly, chiral carbon would mean that all the atoms bonded to that carbon atom are different.

Eg. Butan-2-ol

(ii) If the formation of a more stable intermediate is preferred, hydrolysis of that compound would be easier. So, hydrolysis of 2-chloro butane (CH₃CHClCH₂CH₃) by KOH will result in the formation of secondary carbocation as an intermediate and hydrolysis of chloropropane (CH₃CH₂CH₂Cl) will result in the formation of primary carbocation as an intermediate. We know, secondary carbocation is more stable than primary carbocation due to inductive effect hence hydrolysis of 2-chloro butane by KOH would be easier.

(iii) Iodine is a better leaving group as compared to chlorine because of its large size and less electronegativity, due to which it will be released at a faster rate during the nucleophilic reactions.

Also we know that, S_N2 reactions prefer the formation of a better leaving group, so undergoes S_N2 substitution reactions faster than .