Use the picture to determine if a chemical reaction has occurred. A nail rusting.

Rusting of a nail is a chemical reaction. It occurs when iron in the nail reacts with oxygen from the air and moisture (water) in the environment, leading to the formation of iron oxide (commonly known as rust). This process can be represented by the chemical equation:

\[ 4Fe + 3O_2 + 6H_2O \rightarrow 4Fe(OH)_3 \]

This shows that iron (Fe) combines with oxygen (O2) and water (H2O) to form iron hydroxide, which eventually dehydrates to form rust (iron oxide).

The visible changes, such as the color change of the nail and the formation of a flaky, reddish-brown substance, are indicators of a chemical change. This is confirmed by the fact that rusting changes the chemical composition of the iron, resulting in a new substance. Thus, yes, a chemical reaction has occurred when a nail rusts.