The total number of monobromo derivatives formed by the alkanes with molecular formula is (excluding stereo isomers) ____
Answer: 8
Solution
The three isomers of are:
Total = 3 + 4 + 1 = 8 monobromo derivatives (excluding stereoisomers).
n-Pentane and derivatives 
Isopentane and derivatives 
Neopentane and derivative
- n-Pentane: Has 3 distinct types of H atoms → 3 monobromo derivatives
- Isopentane (2-methylbutane): Has 4 distinct types of H atoms → 4 monobromo derivatives
- Neopentane (2,2-dimethylpropane): Has 1 type of H atom → 1 monobromo derivative
Total = 3 + 4 + 1 = 8 monobromo derivatives (excluding stereoisomers).



JEE Main · 2022 · 25 Jul 2022 · Shift 2 · Integer answer