1. a) chemical properties.
2. a) boiling point.
3. d) freezing point.
4. c) reactivity.
5. a) reactivity.
EXPLANATION:
A physical change is one in which there is no change in composition of substance, however chemical change is one in which there is change in composition of substance. By composition we mean what molecules the substance is made up of. see the pics to understand more.
in boiling, freezing or melting, the substance just changes from solid to liquid or liquid to solid or liquid to gas but there is no change in composition.