# Would it be correct to say that ozone is an element?

My level of chemistry knowledge is restricted to that which is given at high school level.

I was tought that an element is a substance that consists of only one type of atoms, meaning the number of protons is the same for every atom. Is this definition sound?

In case it is sound:

Since ozone gas only consists of oxygen atoms, would it be correct to say that ozone gas, as an entity, is an element?

Would it be more correct to say that ozone is an allotrope of the element oxygen?

Why is it called the table of elements, when it seems that we are actually listing the atoms and not the elements themselves?

• Looks you're thinking too much about definitions ;) And it is one of few allotropes. – Mithoron Sep 16 '15 at 23:49
• Well, it happens that I am interested in having the correct definitions so that I can make precise statements and be sure that I understand things correctly. – Improve Sep 16 '15 at 23:55
• You may call ozone an elementary substance. (Not an element, that's for sure.) – Ivan Neretin Sep 17 '15 at 8:14
• @IvanNeretin Then am I right in assuming that I can't refer to the substance oxygen gas as an element? I understand that this source goldbook.iupac.org/C01022.html claims that it is optional. – Improve Sep 17 '15 at 12:37
• Wow! That's an interesting analogy, though not without certain limitations. We may think of ordinary tin as the canonical allotrope and gray tin as the other one. Now, there are cases when we have a bunch of non-canonical allotropes (like carbon with diamond, fullerenes, nanotubes, lonsdaleite and who knows what else), but then again, one might think of $\sqrt[n]x$ with its complex values... Actually, it's phosphorus where the scheme fails; it has no undisputed canonical allotrope. See, white phosphorus is "canonical" in terms of $\Delta G$, and red phosphorus is the easiest to come by, but... – Ivan Neretin Sep 17 '15 at 21:45