50mL hydrocarbon having 85.7% Carbon at STP on combustio ngives0.37 g CO2 ,0.142g of H2O and unknown qty. of methane.Determine molecular formula of hydrocarbon
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1 Answers
1357% of carbon=85.7%
% fo hydrogen=14.3%
85.7/12=7.14
ratio of C:H is 1:2
so the hydrocarbon is (CH2)n
let the moles of hydrocarbon be x, then x=PV/RT
Let the moles of methane be y
applying POAC on C and H we get
nx=.37/44 + y
2nx=2*0.142/18 + 4y
find n and then molecular mass
