* Chemical change: Involves the formation of new substances with different chemical compositions. For example, burning wood, rusting iron, or cooking an egg.
* Physical change: Alters the form or appearance of a substance but does not change its chemical composition. For example, melting ice, cutting paper, or stretching a rubber band.
Pumping up a tire is a physical change:
* The tire itself remains the same: The rubber, the steel belts, and the other components haven't changed their chemical makeup.
* Only the air pressure inside the tire changes: More air molecules are added, increasing the pressure.
In summary: Pumping up a tire is a physical change because it only affects the air pressure inside the tire, not the chemical composition of the tire itself.
