Molecular Formula Question: Vanillin is the compound containing carbon, hydrogen, and oxygen that gives vanilla beans their distinctive flavor. The combustion of 30.4 mg of vanillin produces 70.4 mg of CO2 and 14.4 mg of H2O. The mass spectrum of vanillin shows a molecular-ion peak at 152 amu. Use this information to determine the molecular formula of vanillin.

Question

anonymous · Answer

I just need the molecular formula i don't care if u show the work

jfraser · Answer

find the mass of C in the CO2, that mass must have come from the sample.

find the mass of H in the H2O, that mass must also have come from the sample.

the remaining mass must be the oxygen that came from the sample.

turn each of those grams into moles

divide those 3 moles by the smallest one of the three and you'll have the smallest molar ratio