Editing Nonmetal (section)

====Higher oxidation states====
:''Roman numerals such as III, V and VIII denote oxidation states''

Some nonmetallic elements exhibit [[oxidation state]]s that deviate from those predicted by the octet rule, which typically results in an oxidation state of –3 in group 15, –2 in group 16, –1 in group 17, and 0 in group 18. Examples include [[ammonia]] NH<sub>3</sub>, [[hydrogen sulfide]] H<sub>2</sub>S, [[hydrogen fluoride]] HF, and elemental xenon Xe. Meanwhile, the maximum possible oxidation state increases from +5 in [[pnictogen|group 15]], to +8 in [[noble gas|group 18]]. The +5 oxidation state is observable from period 2 onward, in compounds such as [[nitric acid]] HN(V)O<sub>3</sub> and [[phosphorus pentafluoride]] PCl<sub>5</sub>.{{efn|Oxidation states do not reflect the actual net charge of atoms in molecules or ions, they represents the valence which refers more to how many bonds there are. For instance carbon typically has a valence of +4, but that only means that it forms three bonds. Electronegative elements such as fluorine are conventionally associated with negative valence, while electropositive ones have positive valence.}} [[Oxidation state#List of oxidation states of the elements|Higher oxidation states]] in later groups emerge from period 3 onwards, as seen in [[sulfur hexafluoride]] SF<sub>6</sub>, [[iodine heptafluoride]] IF<sub>7</sub>, and [[xenon tetroxide|xenon(VIII) tetroxide]] XeO<sub>4</sub>. For heavier nonmetals, their larger atomic radii and lower electronegativity values enable the formation of compounds with higher oxidation numbers, supporting higher bulk [[coordination number]]s.<ref name="Cox" />