Question

a physical change is a change that does not involve a change in the ________ of the substance.
identity
appearance
rewatch

Explanation:

In chemistry (a subfield of Natural Science), a physical change is defined as a change that affects the form or appearance of a substance but not its chemical identity. So the correct term here is "identity" because physical changes don't alter what the substance is (its chemical identity), while appearance can change in physical changes (like melting, freezing, etc.).

Answer:

identity (the option with "identity" should be selected)