1. CnH2n-2 = 14n-2
℅H=mH/M*100=>11,764=(2n-2)/(14n-2)*100=>164,696n-23,528=200n-200=>35,304n=176,472=>n=5
F.M => C5H10 -> ciclopentena
2. CnH2nBr => 14n+80
℅Br=mBr/M*100=>65,57=80/14n+80*100=>n=3.
F.M => C3H6
3. CnH2n+2O => 14n+18
14n............100
14n+18......132,14
=>n=4
F.M => C4H8