Question

A gaseous alkane is exploded with oxygen. the moles of oxygen for complete combustion and carbon dioxide is in the ratio 7:4. deduce molecular formula of the alkane

Answer 1

Volume of oxygen used/volume of carbon dioxide formed
7/4
n=2
alkane is C2H6

Answer 2

Explanation:

General equation for combustion :CxHy + (x+y/4)O2 → xCO2 + y/2H2OAccording to question :(x+(y/4))/x = 7/4Solving the equation we obtain:4x + y = 7x ory=3xy/x = 3/1Thus the alkane is of the type:CxH3xGaseous alkanes are CH4 , C2H6 , C3H8 ,C4H10 only and only gaseous alkane with formula of this type is C2H6