Haven’t you noticed the caption “Shake well before use” in certain medicine bottles?
To which class do the substances in them belong to? (colloid, solution, suspension)

Haven’t you noticed the caption “Shake well before use” in certain medicine bottles? What is the relevance of such instructions on these bottles?

Take 10 mL distilled water in a test tube and take the same volume of hard water in another test tube. Add a few drops of soap solution to both the test tubes and shake well. Do both the test tubes contain the same quantity of foam? Which test tube contains more foam? What do you infer?