## Hydrocarbons and Combustion

Crystal Escobar 1F
Posts: 13
Joined: Fri Sep 25, 2015 3:00 am

### Hydrocarbons and Combustion

When trying to find the empirical formula of a hydrocarbon that combust and produces CO2 and H2O we have to find the mass of carbon and hydrogen but when trying to find the mass of hydrogen in H2O do we use the ratio (1.008/18.015) or (2.016/18.015)?

Thank You

Chem_Mod
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### Re: Hydrocarbons and Combustion

In my opinion, a better approach would be to convert the mass of water collected to moles of water, convert the moles of water to moles of hydrgoen, and then convert moles of hydrogen to grams of hydrogen. This way, you are certain all of your units cancel and you've used the correct ratios.

$(g-H_2O)(\frac{1molH_2O}{18.01gH_2O})(\frac{2molH}{1molH_2O})(\frac{1.00794gH}{1molH})$

This way, you would know that your second ratio is the correct one.