Iron has a density of 7.86 g/cm³. When iron rusts, it forms hydrated Fe₂O₃ that has a density of 5.12 g/cm³. What happens to the material as iron rusts?

Question

Quizplus · Accepted Answer

When iron rusts and transforms into hydrated iron(III) oxide, its density decreases from 7.86 g/cm^3 to 5.12 g/cm^3. This decrease in density means that for the same mass of material, the volume must increase, indicating that the material expands.

Iron Has a Density of 7