Question

1. a nail rusting is an example of a:

physical change
chemical change

Explanation:

Rusting of a nail occurs when iron in the nail reacts with oxygen and water to form iron oxide (rust). This is a chemical reaction that changes the chemical composition of the nail. Physical changes only affect the physical properties like shape, size, or state of matter without changing the chemical identity. Since rusting involves a chemical reaction and change in composition, it is a chemical change.

Answer:

Chemical Change