> Then why do group of atoms (eg. gold) have a color, but not an individual atom? I think the point is the question implicitly assumes you can take an atom, bl

> Then why do group of atoms (eg. gold) have a color, but not an individual atom? I think the point is the question implicitly assumes you can take an atom, blow it up to the size of a softball, and then observe what color the softball is. It's correct to reply that atoms are actually a smaller-scale phenomenon than color, so the color of the softball is "not applicable". (With the correction pointing out that sometimes individual atoms do exhibit "colored" phenomena, although it's not the same as most colors, and doesn't apply to most atoms.) "If the atoms don't have color, why does the substance" is a great philosophical question, similar to the question of why words have meaning, but not letters. By analogy I'd probably start with something like "atoms make color, but that doesn't mean they have it".