Question

Solution
If the alkane, ( C_{x} H_{2 x+2} ) and alkene, ( C_{y} H_{2 y} ) is in the ratio of ( 2: 1, ) then
( M_{operatorname{mix}}=frac{2 .(14 x+2)+1 .(14 y)}{3}=20 )
( 28 x+14 y=56 )
If the alkane, ( C_{x} H_{2 x+2} ) and alkene, ( C_{y} H_{2 y} ) is in the ratio of ( 1: 2, ) then
( M_{m i x}=frac{1 .(14 x+2)+2 .(14 y)}{3}=24 )
( 14 x+28 y=70 )
Solving equation (1) and ( (2), ) we get ( x=1, y=2 )

# . in a gaseous mixture, if an alkane (CxHx. 2) and an alkene (CyH2v) are taken in 2:1 mole ratio, the average molecular weight of mixture is observed to be 20. If the same alkane and alkene are taken in 1:2 mole ratio, the average molecular weight of mixture is observed to be 24. Then, the value of 'X and 'y' are respectively : (A) 2,1 (B) 1, 2 (C) 2,3 (D) 3,2

Solution