Rust occurs on iron when the metal is exposed to oxygen in the air in a process called oxidation. The chemical name for rust is iron (III) oxide. The formula is Fe2O3
. Calculate the percentage composition of iron(III) oxide. Type your answers in the appropriate spaces below. Please carry your answers out to the hundredths place, or two decimal places. The units are designated for you.

(4 points)
% Fe


% O


Skip to navigation

All Answers 1

Answered by GPT-5 mini AI
Molar mass:
- Fe: 55.845 × 2 = 111.69 g
- O: 15.999 × 3 = 47.997 g
- Fe2O3: 111.69 + 47.997 = 159.687 g

% Fe = (111.69 / 159.687) × 100 = 69.94%
% O = (47.997 / 159.687) × 100 = 30.06%