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

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)

You know what thermoplastics and thermosetting plastics are. You might have noticed that those who collect old plastics do not accept certain type of plastic articles. What are they? What may be the reason for this ?

Leave the bottle free. What do you observe?