-1 is most common, though oxidation number up to +7 are known (except for fluorine)
Group 1 elements have an oxidation number of +1, group 2 elements have an oxidation number of +2, group 17 elements have an oxidation number of -1, and group 18 elements (noble gases) have zero oxidation number since they are chemically unreactive.
The oxidation number of iodide is -1. Iodine is in Group 17 of the periodic table, commonly known as the halogens, which typically have an oxidation number of -1 when in ionic compounds.
-1.
The oxidation number for K in KCl is +1, as alkali metals (Group 1 elements) typically have a +1 oxidation state. For Cl in KCl, the oxidation number is -1, as halogens (Group 17 elements) typically have a -1 oxidation state when they form ionic compounds.
The halogens (group 17) have an oxidation number of -1, though the halogens below fluorine can have other oxidation numbers as well. Hydrogen can also have an oxidation number of -1 when it forms hydrides.
Elements with fixed oxidation numbers include alkali metals (group 1 elements) which have a +1 oxidation state, alkaline earth metals (group 2 elements) which have a +2 oxidation state, and nonmetals in group 17 (halogens) which have a -1 oxidation state in compounds.
Group 1 elements have an oxidation number of +1.
The oxidation number of group 17 elements, also known as the halogens, is typically -1. This is because they have seven valence electrons and tend to gain one electron to achieve a full outer shell configuration.
The oxidation number for fluoride is -1. Fluorine, which is present in fluoride compounds, is in group 17 of the periodic table and typically has an oxidation state of -1 when bonded to other elements.
The oxidation number of fluoride is -1. Fluorine is a group 17 element and tends to gain one electron to achieve a full outer shell, giving it a -1 oxidation state in most compounds.
Group 1 or alkali metals (+1 oxidation number). Group 2 or alkaline earth metals (+2 oxidation number).
Elements that have a single oxidation number include group 1 elements (e.g. sodium, potassium) which have an oxidation number of +1, and group 2 elements (e.g. magnesium, calcium) which have an oxidation number of +2.