When iron is exposed to moist air, it gradually rusts. This is due to the formation of?
A
hydrate iron (III) oxide
B
anhydrous iron (III) oxide
C
anhydrous iron (II) oxide
D
hydrate iron (II) oxide
Verified Correct Answer: A.
Step-by-Step Mathematical Solution
Rusting is an oxidation reaction. The iron reacts with water and oxygen to form hydrated iron(III) oxide, which we see as rust.
Source: WAEC / JAMB / NECO Classroom Archive (Record #4495)