Naphthalene, commonly known as moth balls, is composed of 93.7% carbon and 6.3% hydrogen.

determine the empirical for naphthalene.
molecular formula for Naphthalene. Determine the number of empirical formulas you would need to make a full naphthalene molecule.

3 answers

Take a 100 g sample which will give you
93.7 g C
6.3% H.
Convert each to mols.
93.7/12 = ?
6.4./1 = ?
Now find the ratio of the two and that gives the empirical formula. There isn't enough information to find the molecular formula.
1. 93.7g C x mole/12.00g C =7.8
6.3g H x mole/1.01g H =6.23

2. divide the smallest number. (6.23)
H 6.23/6.23 =1
C 7.8/ 6.2= 1.25

3. Multiply by 4.
H 1x4 = 4
C 1.25x4 = 5

4. Empirical formula is C5H4
Why multiply by 4???