General Chemistry

An unknown compound has a formula of CxHyOz. You burn 0.1523 g of the compound and isolate 0.3718 g of CO2, and 0.1522 g of H2O. What is the empirical formula of the compound? If the molar mass is 72.1 g/mol what is the molecular formula?

asked by Jashmid
  1. Convert 0.3718 g CO2 to g carbon, then find percent C = (mass C/mass sample) * 100 = ??

    Same process convert 0.1522 g H2O to grams hydrogen (atoms) and find percent H.

    Find percent oxygen by
    100% - percent H = percent C

    Take a 100 g sample which will give you the percents of the three elements as grams; i.e., 27.0 %C and 18.0%H (numbers I just made up) will give 27.0 g C and 18.0g H.
    Find moles C, H, and O by dividing the grams by the molar mass C, H, or O.

    Now find the molar ratio of the three elements to each other with the smalles value being 1.00. The easy way to do this is to divide the smallest number by itself (which, of course, will be 1.0000000). Then divide the other number by the same small number, round to whole numbers and substitute into the CxHyOz. That will give you the emprical formula.

    To find the molecular formula take the formula mass of the empirical formula and divide that into 72. The resultant will tell you how many units of the empirical formula are in the molecular formula.
    Post your work if you get stuck.

    posted by DrBob222
  2. C6HO2

    posted by Becca

Respond to this Question

First Name

Your Answer

Similar Questions

  1. CHEMISTRY

    A compound which contains hydrogen, oxygen, carbon only has molar mass of about 85 g/mol. When 0.43 g of the compound is burned in excess of oxyfen, 1.10 g of CO2 and 0.45 g of H2O are formed. Find the molecular formula and the
  2. Chemistry grade 11

    An organic compound is composed of C, H and O. A 0.1005 g sample of this is combusted, producing 0.2829 g CO2 and 0.1159 g of H2O. What is the empirical formula of this compound? If the compound has a molar mass of 14 g/mol. What
  3. Chemistry

    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
  4. 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
  5. 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
  6. Chemistry

    An unknown compound contans only C, H, and O. Combustion of 5.70 g of this compound produced 11.4g of CO2 and 4.66g of H2O. What is the empirical formula of the unknown compound? CHO
  7. Chemistry

    An unknown compound contains only C, H, and O. Combustion of 4.50 g of this compound produced 10.2 g of CO2 and 4.19 g of H2O. What is this empirical formula of the unknown compound?
  8. Chemistry

    A compound isolated from oil of mint has a characteristic cool, refreshing odour. It is frequently used in cough drops to ease the pain of a sore throat. This compound contains only C, H, and O. If 95.6 mg of this compound burns
  9. Chemistry

    A compound isolated from oil of mint has a characteristic cool, refreshing odour. It is frequently used in cough drops to ease the pain of a sore throat. This compound contains only C, H, and O. If 95.6 mg of this compound burns
  10. Chemistry

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

More Similar Questions