# Chemistry

posted by .

Combustion analysis of 0.343 g of a compound containing C, H, and O produces 0.753 g of CO2 and 0.411 g of H2O. Mass spectral analysis shows that the compound has a molar mass around 120 g mol-1. What is the compound's:
Empirical Formula:-----
Molecular Formula:-----

• Chemistry -

The problem doesn't tell you how much oxygen so you must calculate that.
Convert 0.753 g CO2 to grams C.
Convert 0.411 g H2O to grams H.
Add those two and subtract from 0.343 to find grams oxygen.

Now convert each of those grams to moles.
g C/12 = moles C
g H/1 = moles H
g O/16 = moles O.

Find the ratio in small whole numbers to each other. An easy way to do that is to divide the smallest number by itself which assures you of getting 1.0000 for that one, then divide all the other numbers by that same small number. Round to the nearest whole number to obtain the empirical formula. Determine the mass of the molecule as if the empirical formula is the molecular formula. The problem gives additional information that the molecular formula is approximately 120; therefore, 120/your empirical formula mass = some number which you should round to the nearest whole number (which I will call x). Then the compounds molecular formula will be (empirical formula)x.
To check your values, I obtained C3H8O for the empirical formula, x of 2 to make the molecular formula C6H16O2. Post your work if you get stuck.

## Similar Questions

1. ### ap chemistry

18. Answer the following question that relate to the analysis of chemical compounds. (a) A compound containing the elements C, H, N, and O is analyzed. When a 1.2359g sample is burned in excess oxygen, 2.241g of CO2(g) is formed. The …
2. ### chemistry

Combustion analysis of 0.213 g of a compound containing C, H, and O produces 0.468 g of CO2 and 0.255 g of H2O. Mass spectral analysis shows that the compound has a molar mass around 120 g mol-1. What is the compound's: Empirical Formula:(-------) …
3. ### Chemistry

Combustion analysis of 0.284 g of a compound containing C, H, and O produces 0.623 g of CO2 and 0.340 g of H2O. Mass spectral analysis shows that the compound has a molar mass around 120 g mol-1. What is the compound's: Empirical Formula: …
4. ### Chemistry

A compound containing only C, H, and O was extracted from the bark of the sassafras tree. The combustion of 36.3mg produced 98.6 of CO2 and 20.2mg of H2O. The molar mass of the compound was 162 g/mol. Determine its empirical and molecular …
5. ### Chemistry

A compound containing only C, H, and O was extracted from the bark of the sassafras tree. The combustion of 36.3mg produced 98.6 of CO2 and 20.2mg of H2O. The molar mass of the compound was 162 g/mol. Determine its empirical and molecular …
6. ### Chemistry

2) What is the empirical formula of a compound containing C, H, O if combustion of 1.23g of the compound yields 1.8g CO2 and .74g of H2O 3) What are the empirical and molecular formulas of a hydrocarbon if combustion of 2.10g of the …
7. ### Science

The combustion of a compound which contains only C and H yields 2.58 g of CO2 and 0.53 g of H2O. What is the empirical formula of the compound?
8. ### Chemistry

Hey, can someone help me with this? A compound containing only C, H and O was subjected to combustion analysis. A sample of 6.120Ã—10^-2 g produced 1.601Ã—10^-1 g of CO2 and 5.243Ã—10^-2 g of H2O. Determine the empirical formula
9. ### CHemistry

What is the molecular formula of glycerol (a compound containing C, H, and O) from the following combustion analysis: when 2.00 g glycerol are combusted, 2.865 g CO2 and 1.564 g H2O are recovered. I already found uts molar mass its …
10. ### chemistry

A 8.408 gram sample of an organic compound containing C, H and O is analyzed by combustion analysis and 12.53 grams of CO2 and 3.849 grams of H2O are produced. In a separate experiment, the molar mass is found to be 118.1 g/mol. Determine …

More Similar Questions