The best test would be doing a double-blind test between the person who is receiving the medicine so that they don't know if they received a placebo or not and the person giving the medicine does not know if the participant is receiving a placebo or not.
However, a placebo test can simply be done. This is where the patient received a medicine that does not have any medicinal effects and see if the person sleeps better. If they say they did, they have fallen under the placebo effect.
The physical changes can alter the form of a substance but does not necessarily change it to an other substance
Explanation:
The physical properties of matter is one that does not depend on composition.It just change the form of matter into another form with changing into composition.
Physical properties include: appearance, texture, color, odor, melting point, boiling point, density, solubility, polarity, and many others.
The three states of matter are: solid, liquid, and gas. The melting point and boiling point are related to changes of the state of matter. All matter may exist in any of three physical states of matter.
Example:
When water is boiled then it change into vapors. Now the form of water is change but its composition is same like water
When water freezes into ice, now phase are different i.e water is liquid while ice is solid but both have same composition.
