Why is it important to know what things are made of

Explanation:

Knowing what things are made of, especially in the case of a mixture whose constituents still retain there chemical properties, assists in knowing the beneficial and harmful effects of those things.

For a example, a body cream/lotion (a mixture) that contains hydroquinone will give an individual the idea that the body cream is a lightening cream; as hydroquinone is a depigmenting agent that reduces the production of melanin thereby leading to the lightening of the skin.

Another relevant example is the hand sanitizer that is recommended for use of cleaning of hands in order to rid the hands off of corona virus. The recommended hand sanitizer should be made of at least 60% ethanol for effective use (which dissolves the virus). Knowing the components of a sanitizer to be used against the virus will assist an individual at a store make informed decision about purchase.