Finding the empirical and the molecular formula?

Question

2.4g of a compound of carbon, hydrogen and oxygen on combution gave 3.52g of CO2 and 1.44 H20. The Mr of the compound was found to be 60.
What are the masses of carbon, hydrogen and oxygen in 2.4g of the compound?
What are the empirical and molecular formulae of the compound?

Answer 1

Given: 2.4g CHO combust to form 3.52g CO2 and 1.44g H2O

Bal Formula: 2CHO + O2 ------> H20 + 2CO2

Mol C= (3.52g CO2) (1 mol CO2/44.0g CO2) (1 mol C/ 1 mol CO2) = 0.080 mol C

Mol H= (1.44g H20) ( 1 mol H20/ 18.0 g H20) (2 mol H/ 1 mol H20) = 0.16 mol H

Mass C= (0.080 mol C) (12.0g C/ 1 mol C) = 0.96g C

Mass H= (0.16 mol H) (1.0g H/ 1 mol H) = 0.16g H

Mass O= Mass of substance - (Mass of C + Mass of O)

Mass O= 2.4g - (0.96g +0.16g)
Mass O= 2.4g - (1.12g)

Mass O= 1.28g


Mol O= (1.28g O) (1 mol O/ 16.0 g O) = 0.08 mol O

---Empirical Formula---
For C
0.08/0.08 = 1

For H
0.16/0.08 = 2

For O
0.08/0.08 = 1

Empirical Formula= CH2O

----Molecular Formula----

MW/FW

60g/30g=2

Molecular Formula = C2H4O2 or (CH2O)2

*Summary*
Mass Carbon= 0.96g
Mass Hydrogen= 0.16g
Mass Oxygen= 1.28g
Empirical Formula= CH2O
Molecular Formula= C2H4O2 or (CH2O)2

Answer 2

Molecular formula inform you the way many atoms of each ingredient are in a compound, and empirical formula inform you the finest or maximum decreased ratio of components in a compound. If a compound's molecular formula can not be decreased to any extent further, then the empirical formula is an identical by way of fact the molecular formula.

Answer 3

0.16 g H
1.12 g C
1.28 g 0

Empirical formula is C2H4O2. Molecular is OHCH2CH2OH?