A physical property is an aspect of matter that can be observed or measured without changing it. Examples of physical properties include color, molecular weight and volume.
A chemical property may only be observed by changing the chemical identity of a substance. This property measures the potential for undergoing a chemical change. Examples of chemical properties include reactivity, flammability and oxidation states.
Chemical change can be noticed when the color or temperature changes, precipitates form, gas is produced, and/or light comes from it. It is very difficult to reverse this kind of change.
Physical change can be noticed if the state of matter has changed. It is very easy to reverse this type of change.