Respuesta :

Abbygal
Rust forms when oxygen reacts with chemicals in rocks, and that is often the case with many other elements in general. Like a copper nail being exposed to the air will rust.

Answer : Rust forms when oxygen reacts with chemicals in rocks.

Explanation :

Rusting : It is a chemical process in which an iron react with oxygen to give an iron(III)oxide as a product. The product iron(III)oxide formed from the chemical reaction is known as rust.

The chemical reaction will be,

[tex]4Fe+3O_2\rightarrow 2Fe_2O_3[/tex]

Hence, rust forms when oxygen reacts with chemicals in rocks.