Question

which of these is an example of a physical change?
water freezing into ice cubes
a piece of paper burning
a penny turning green when exposed to air
a metal pipe rusting

Explanation:

A physical change is a change in which the substance's physical form changes, but its chemical composition remains the same. Water freezing into ice cubes is a phase - change from liquid to solid without altering the chemical formula (H₂O). Burning paper, a penny turning green, and a metal pipe rusting are chemical changes as new substances are formed.

Answer:

Water freezing into ice cubes