Answer to Question #127795 in Organic Chemistry for Oredola Abdulbaasit

Question

write the balance equation for the complete combustion, in oxygen of the gaseous compounds (i) an alkane and (ii) alkyne each of which contains n-carbon atoms in molecules. Equal volume of the two hydrocarbon , measured at 120 degree celcius ,were separetely completely combusted in oxygen. The volume steam produced in (i) and (ii) were in the ratio 5:2 . Determine the value of "n" and hence the formulae of the alkane and alkyne

Answer 1

Balance equation of complete combusation, in oxygen of the

(i) alkane C_nH_2n+2 + (3n+1)/2 O₂ = n CO2 + (n+1) H₂O

(ii) alkyne C_nH_2n-2 + (3n-1)/2 O₂ = n CO2 + (n-1) H₂O

(n+1)/(n-1) = 5/2

3n = 7

n = 2.33 approximate 2 (Answer)

Formula of (i) alkane = C₂H₆ (ii) alkyne = C₂H₄