hapetusluvuille

Hapetusluvuille, known in English as oxidation states or oxidation numbers, are a bookkeeping tool used in chemistry to track the hypothetical charge an atom would have if all its bonds to atoms of different elements were purely ionic. It is a conceptual number, not a real charge, assigned to an atom in a molecule or ion. The sum of the oxidation states of all atoms in a neutral molecule is zero, and in a polyatomic ion, it equals the charge of the ion. There are several rules for assigning oxidation states. For example, elements in their elemental form always have an oxidation state of zero. In compounds, alkali metals (Group 1) have an oxidation state of +1, and alkaline earth metals (Group 2) have an oxidation state of +2. Fluorine always has an oxidation state of -1. Oxygen usually has an oxidation state of -2, except in peroxides where it is -1 and when bonded to fluorine. Hydrogen typically has an oxidation state of +1 when bonded to nonmetals and -1 when bonded to metals. The assignment of oxidation states is crucial for understanding redox reactions, where electrons are transferred between species. Changes in oxidation states indicate whether a species has been oxidized (oxidation state increases) or reduced (oxidation state decreases).