Why is oxygen usually in the form O2?
Dear Straight Dope: Why is breathable oxygen O2? I know that O3 is ozone and is toxic. Whatever happened to O1? Why does it have to be in a bond of two oxygen molecules for us to be able to use it? — Terry in Vegas This question isn’t easy to answer, but that never stopped us at the Straight Dope Science Advisory Board. Grab a drink, sit down, and try to follow along. First of all, we need to understand something about atomic structure. For the purposes of this article, the simple classic model will do, where protons and neutrons occupy the center of the atom (known as the “nucleus”) and electrons buzz around them in a cloud (known as “orbitals”). Protons are positively charged particles and neutrons have no charge, giving the nucleus an overall positive charge. Electrons have a negative charge. In an atom with an overall charge of zero, there are as many electrons as protons. Stay awake, the answer’s coming up. The number of protons determines what element an atom is. If we could some
