Answer to Question #185942 in Chemistry for ary

Question

The iron in an organometallic compound was determined by treating a 0.5324 g sample with HNO3 and heating to volatilize the organic material. After ignition, the residue of Fe2O3 weighed 0.1982 g.What is the %w/w Fe in this compound?

Answer 1

Solution:

The molar mass of Fe is 55.845 g/mol

The molar mass of Fe₂O₃ is 159.69 g/mol

2Fe → Fe₂O₃

Mass of Fe = (0.1982 g Fe₂O₃) × (55.845 g Fe / 159.69 g Fe₂O₃) × (2/1) = 0.1386 g Fe

The %w/w Fe in the sample, therefore, is

%Fe = (0.1386 g Fe / 0.5324 g sample) × 100% = 26.033%

%Fe = 26.033%

Answer: The %w/w Fe in the compound is 26.033%.