Answer:
Iron
Explanation:
The only substance that cannot be broken down by a chemical change is Iron.
Iron is an element and elements are made up of atoms. Atoms are the smallest indivisible particles that takes part in chemical reactions.
- Other choices are compounds.
- Compounds are made by combining atoms together through the loss, gain or sharing of electrons.
- This interaction creates bonds between two or more species.
- But for substances made up of atoms alone, no bonds are formed and hence, they cannot be further broken down.
