Question

Iron combines with oxygen and water from the air to form rust. If an iron nail were
allowed to rust completely, one should find that the mass of the rust:

Answer 1

Answer:

When iron rusts - in the presence of moisture and oxygen - iron-oxide is formed. Iron oxide is nothing but a compound of iron and oxygen. There is an increase in the mass of the iron equal to the mass of oxygen that has gone into forming the rust.

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