* State of Matter: Solid metal changes to liquid metal. The metal atoms themselves remain the same, they just rearrange and move more freely.
* Chemical Composition: The chemical bonds and the arrangement of atoms within the metal don't change. It's still the same element or alloy.
Examples:
* Melting ice: Ice (solid water) melts into liquid water, but it's still H2O.
* Heating iron: Solid iron melts into liquid iron, but it's still Fe.
Contrast with Chemical Changes:
* Burning wood: Wood reacts with oxygen, producing ash, smoke, and gases. The chemical composition changes entirely.
* Rusting iron: Iron reacts with oxygen and water to form iron oxide (rust). This is a new compound with a different chemical composition.
In short, melting metal is a physical change because it only alters the physical state of the metal, not its chemical makeup.
