Benzene is a liquid compound composed of carbon and hydrogen. A sample of benzene weighing 342 mg is burned in excess oxygen and forms 1156 mg of carbon dioxide. What is the percent composition of benzene?

If a compound contains oxygen as well as carbon and hydrogen, the mass of the oxygen can be determined by subtracting the masses of the carbon and the hydrogen from the total mass of the compound.

mass of O = mass of compound – [mass of C + mass of H]

n-Butyl phthalate is used as an insect repellant and is composed of carbon, hydrogen, and oxygen. When a 0.3413 g sample was subjected to combustion analysis, 0.2430 g of water and 0.8633 g of carbon dioxide were produced. In another analysis, the molecular weight was determined to be 278.38 g/mol. Calculate the empirical formula and the molecular formula.

[empirical formula = C₈H₁₁O₂ & molecular formula = C₁₆H₂₂O₄]

When a 1.0000 g sample of a vitamin C was combusted, 1.4991 g of CO₂ and 0.4092 g of H₂O were isolated. Calculate the percent composition and empirical formula of vitamin C.

[40.909% C, 4.587% H, 54.504% O & empirical formula = C₃H₄O₃]

In another analysis the molecular mass of vitamin C was found to be 176.14. What is the molecular formula of vitamin C? [C₆H₈O₆]

A 1.500 g sample of hydrocarbon undergoes complete combustion to produce 4.400 g of CO₂ and 2.700 g of H₂O. What is the empirical formula of this compound? [CH₃]

A 0.250 g sample of hydrocarbon undergoes complete combustion to produce 0.845 g of CO₂ and 0.173 g of H₂O. What is the empirical formula of this compound? [CH]

A 0.1034 g sample of a compound composed of carbon, hydrogen and oxygen is subjected to combustion analysis, producing 0.2351g CO₂ and 0.0962 g H₂O. What is the empirical formula for the compound? [C₃H₆O]

If the molecular weight is 116.18 g/mol, what is the molecular formula?

[C₆H₁₂O₂]