The empirical formula of the compound : Cu₂O
Given
66.41 g Cu
8.56 g O
Required
The empirical formula
Solution
1. Find mol
mol = mass : Ar
mol = 66.41 : 63.5
mol = 1.046
mol = 8.56 : 16
mol = 0.535
2. mol ratio
Cu : O (divide by smallest mol⇒0.535) :
[tex]\tt \dfrac{1.046}{0.535}\div \dfrac{0.535}{0.535}=2\div 1[/tex]