The general formula of an alkane is CnH2n+2.
The balanced chemical equation for the complete combustion of an alkane is:
CnH2n+2+(23n+1)O2→nCO2+(n+1)H2O
Given that 1 mole of the alkane requires 8 moles of oxygen for complete combustion, we equate the stoichiometric coefficient of O2 to 8:
23n+1=8
3n+1=16
3n=15
n=5
The molecular formula of the alkane is C5H12.
The number of carbon atoms is 5 and the number of hydrogen atoms is 12.
Sum of the number of carbon and hydrogen atoms =5+12=17.
Answer: 17