When iron rusts, its weight

Solution (By Examveda Team)

When iron rusts, its weight increases.

Rusting is a type of oxidation reaction where iron reacts with oxygen in the presence of water or moisture in the air.

The chemical reaction can be summarized as follows:

4Fe + 3O₂ + 6H₂O → 4Fe(OH)₃

The product of this reaction is iron(III) hydroxide, which further dehydrates to form iron(III) oxide, commonly known as rust.

During rusting, iron atoms combine with oxygen molecules from the air to form iron oxide.

This means that additional mass from oxygen is added to the iron, resulting in an increase in the overall weight of the iron object.

This process is not only a chemical change but also a physical one, as the rust occupies more volume than the original metal.

The increase in weight occurs because of the mass of the oxygen that has combined with the iron.

Therefore, when iron rusts, the addition of oxygen causes the weight of the iron to increase.