What is the empirical formula of the compound?

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To determine the empirical formula of a compound containing carbon, hydrogen, and oxygen, start by calculating the grams of carbon and hydrogen produced from the combustion products CO2 and H2O. For CO2, the calculation yields approximately 0.233 g of carbon, while H2O provides about 0.0194 g of hydrogen. The remaining mass of the original sample can be attributed to oxygen by subtracting the masses of carbon and hydrogen from the total sample weight. This process allows for the determination of the mole ratio of each element, leading to the empirical formula. Understanding these stoichiometric calculations is essential for solving such chemistry problems.
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A 0.4647-g sample of a compound known to contain only carbon, hydrogen, and oxygen was burned in oxygen to yield 0.8635 g of CO2 and 0.1767 g of H2O. What is the empirical formula of the compound? I don't know how to figure this out without percentages of each element.
 
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i can help you! i can help you!

yeah..this is one of those hard stochiometry problems. but nofear; my teacher told us how to do these a month ago, so i can help you :)

kk..you have to think of it like this:
CxHyOz ---> CO2 + H2O

so for CO2, you find the grams of carbon by...
(12.01 g C) / (44.01 g CO2) = 0.27 g (0.8635) = 0.233 g C in CO2
and for H2O, you do the same thing...
(2.02 g H) / (18.02 g H2O) = 0.11 g (.1767) = 0.0194 g H in H2O
and for O, you do...
(0.4647) - (0.233+0.0194) = and get grams of O
and then you can do the rest...i'm getting tiredd lol.

hope that helped! :biggrin:
 
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