Number of bromo derivatives obtained on treating ethane with excess of Br2, in diffused sunlight is...
Answer: 9
Solution
Free-radical bromination of ethane with excess bromine replaces hydrogen atoms successively, and every distinct structural arrangement is counted. One monobromo product, CH3CH2Br, is possible. Two dibromo products arise, CH3CHBr2 and CH2BrCH2Br. Two tribromo products form, CH3CBr3 and CH2BrCHBr2. Two tetrabromo products form, CHBr2CHBr2 and CH2BrCBr3. One pentabromo product, CHBr2CBr3, and one hexabromo product, CBr3CBr3, complete the set. Adding these gives 1+2+2+2+1+1=9 bromo derivatives.