Question

what happens when a substance undergoes a physical change? some physical properties change, but the substance keeps its identity. no physical properties change, and the substance keeps its identity. some physical properties change, and the substance changes its identity. no physical properties change, but the substance changes its identity.

Explanation:

A physical change alters observable physical properties (like shape, state, or size) of a substance but does not modify the chemical composition or fundamental identity of the substance. For example, melting ice (solid water to liquid water) changes the state (a physical property) but the substance remains water.

Answer:

Some physical properties change, but the substance keeps its identity.