## Yahoo! 3 years ago Complete combustion of 5.90 g of a hydrocarbon produced 18.8 g of CO2 and 6.75 g of H2O. What is the empirical formula for the hydrocarbon?

1. Yahoo!

@ganeshie8 @Rohangrr

2. Yahoo!

@Vincent-Lyon.Fr

3. Rohangrr

302 is thwe diameter

4. Yahoo!

Lol...@Rohangrr Wat Do u Mean..)

5. Rohangrr

lol

6. Yahoo!

Any Idea @Vincent-Lyon.Fr

7. Vincent-Lyon.Fr

It is very easy, and you do not even need the information about the 5.9 g of hydrocarbon. It is just a matter of proportionality. Look how you solve this kind of problem. 1. Write general chemical equation: $$\large C_nH_m+xO_2\rightarrow nCO_2+\frac m2 H_2O$$ 2. Work out proportionality of masses using molar masses 44 g/mol for carbon dioxide and 18 g/mol for water: Mass of $$CO_2$$ produced is 44n Mass of $$H_2O$$ produced is 18m/2 = 9m Hence: $$\Large \frac{44n}{9m} = \frac{18.8}{6.75}$$ => $$\Large \frac mn = \frac 74$$ 3. After rearranging for a simple fraction 7/4 : Empirical formula is $$C_4H_7$$

8. Yahoo!

Thxxx...)

9. Vincent-Lyon.Fr

Note: if mass of oxygen used is mentioned, you might have to write the stoichiometric coefficient for oxygen as n + m/4 I was just lazy because is was not useful in your example !

10. Yahoo!

Ok....)