superoxide
Quick Summary
A superoxide is a chemical compound containing the monovalent anion O2−. In the superoxide ion, oxygen has an oxidation state of −½. The stability of metal superoxides depends on the size and electropositive character of the metal; larger, more electropositive metals form more stable superoxides. Potassium, rubidium, cesium, strontium, and barium form stable superoxides when burned in oxygen. These compounds are yellow to orange paramagnetic solids and are strong oxidizing agents that react vigorously with water to produce oxygen gas and hydroxide ions.12
Molecular oxygen (O2), while essential for life, can also be toxic. Its reduction process can produce superoxide (O2−), hydrogen peroxide (H2O2), and hydroxyl radicals (HO•). These intermediates can damage cellular components and lead to DNA damage. Humans have defense systems, like superoxide dismutase enzymes, to convert superoxide into oxygen and hydrogen peroxide, and other enzymes to break down hydrogen peroxide into oxygen and water.3
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oxideMetal oxides…covalent single bonds, and (3) superoxides, containing superoxide ions, O2−, which also have oxygen-oxygen covalent bonds but with one fewer negative charge than peroxide ions. Alkali metals (which have a +1 oxidation state) form oxides, M2O, peroxides, M2O2, and superoxides, MO2. (M represents a metal atom.) The alkaline earth metals…
Read More…covalent single bonds, and (3) superoxides, containing superoxide ions, O2−, which also have oxygen-oxygen covalent bonds but with one fewer negative charge than peroxide ions. Alkali metals (which have a +1 oxidation state) form oxides, M2O, peroxides, M2O2, and superoxides, MO2. (M represents a metal atom.) The alkaline earth metals…
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In the superoxide ion, O2−, the oxygen has an oxidation number of −1/2. The stability of metal superoxides depends on the size and the electropositive character of the metal. The larger the metal and the more electropositive it is, the greater the stability of…
Read MoreIn the superoxide ion, O2−, the oxygen has an oxidation number of −1/2. The stability of metal superoxides depends on the size and the electropositive character of the metal. The larger the metal and the more electropositive it is, the greater the stability of…
Read More