* No new substance is formed: Magnetizing iron doesn't change the chemical composition of the iron. It simply aligns the magnetic domains within the iron, which are already present.

* The change is reversible: You can demagnetize iron by heating it or exposing it to a strong alternating magnetic field. The iron returns to its original state.

Here's a contrast with a chemical change:

* Chemical change: A change that results in a new substance being formed. For example, rusting iron (iron reacting with oxygen to form iron oxide) is a chemical change.

Let me know if you have any other questions!