Finding the empirical formula of a hydrocarbon from CO2 produced

[darthxepher]

Homework Statement

A whole class of compounds is composed of just carbon and hydrogen, the "hydrocarbons". If a 7.81 g sample of a hydrocarbon was analyzed and the carbon was converted to 26.4g of CO2 what is the empirical formula?

Homework Equations

No clue what converted means... and how a part of the sample increases in mass...

The Attempt at a Solution

Choices

a) CH b)CH10 c)C2H10 d)C10H e)C10H2

 

[Borek]

I see your confusion.

7.81 g of hydrocarbon was burnt in exess oxygen, 26.4 g of CO₂ were produced.

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methods

 

[symbolipoint]

"Converted" means the hydrocarbon reacted with oxygen at a high temperature, and the carbon was all burned to carbon dioxide.