Question

A sample of black mineral hematite, an oxide of iron found in many iron ores, contains 34.97g of iron and 15.03g of oxygen. what is the empirical formula of hematite?​

Answer 1

The empirical formula : Fe₂O₃

Further explanation

Given

34.97g of Iron

15.03g of Oxygen

Required

The empirical formula

Solution

Mol ratio :

Fe(Iron) : 34.97 g : 56 g/mol = 0.624

O(Oxygen) : 15.03 g : 16 g/mol = 0.939

Divide by 0.624 :

Fe : O = 1 : 1.5

Fe : O = 2 : 3