Oxides boron family elements

If oxygen is present in a flame, the formation of stable oxides with free metal atoms can remove a large percentage of the metal atoms from the flame. For example, free magnesium atoms in a flame can readily form MgO if oxygen is present. The dissociation energy of MgO is approximately 7.9 eV and it has been calculated that MgO is only about 1.4% dissociated in an air-acetylene flame ( 2200°C). All of the alkaline earth elements readily form oxides and, as a family, are especially subject to this type of interference. Aluminum and boron, in family IIIA, also form stable oxides in most flames. 

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