Question

Empirical formula of an oxide of metal which has 69.9% metal (M) and 30.1% oxygen by mass(Atomic mass M-55.85 amu, O=16.00 amu)​

Answer 1

Answer:

Explanation:

100 g of the compound contains 69.9 g iron and 30.1 g oxygen.

The atomic masses of iron and oxygen are 55.85 amu and 16.00 amu.

The number of moles of Fe present in 100 g of compound are  

55.85

69.9

​  

=1.25  

The number of moles of O present in 100 g of compound are  

16.00

30.1

​  

=1.88  

The mole ratio of Fe to O is  

1.88

1.25

​  

=0.67:1 or 2:3

Hence, the empirical formula is Fe  

2

​  

O  

3

​