A combustion device was used to determine the empirical formula of a compound containing only carbon, hydrogen, and oxygen. A 0.6349 g sample of the unknown produced 1.603g of CO2 and 0.2810g H20. Determine the empirical formula of the compound.

Question

A combustion device was used to determine the empirical formula of a compound containing only carbon, hydrogen, and oxygen.  A 0.6349 g sample of the unknown produced 1.603g of CO2 and 0.2810g H20.  Determine the empirical formula of the compound.

abmon98 · Answer

Mass fraction: 12/44=0.27
0.27*1.603=0.437grams of C in CO2
Molar Mass of H2O:18grams
Mass fraction of Hydrogen in H2O: 2/18=0.111
0.111*0.2810=0.03
grams in original compound: 0.6349-(0.437+0.111)=0.1678 grams of Oxygen
0.437/12=0.036
0.03/1=0.03
0.1678/16=0.01048
Divide by the smalles figure 
C3H3O