Consider all the structural isomers with molecular formula C ₅ H ₁₁ Br are separately treated with KOH ( aq ) to give respective substitution products, without any rearrangement. The number of products which can exhibit optical isomerism from these is _ _ _ _ .

Step-by-step solution

For C₅H₁₁Br structural isomers to show optical isomerism after KOH substitution (Br→OH), the resulting product must have a chiral center (asymmetric carbon with four different groups). Possible carbon skeletons: n-pentane, 2-methylbutane, 2,2-dimethylpropane. Analysis of isomers: 2-bromopentane → CH₃CHOHCH₂CH₂CH₃: C2 bonded to H, OH, CH₃, and CH₂CH₂CH₃ (chiral). 3-bromopentane → CH₃CH₂CHOHCH₂CH₃: C3 bonded to H, OH, CH₂CH₃, CH₂CH₃ (NOT chiral). 3-bromo-2-methylbutane → CH₃CH(CH₃)CHOHCH₃: Chiral center present. 1-br