ABSTRACT

Researchers encountered the phenomenon of the formation of an active intermediate during

the oxidation of metals and organic compounds in the middle of the 19th century. Shonbein

was the first to discover ozone formation in a slow oxidation of phosphine [1], diethyl ether,

and ethyl alcohol [2]. He observed the oxidation of hydrogen iodide into diiodine and

oxidation of indigo that accompanied the oxidation of Zn, SO2, FeO, H2S, AsH3, SbH3,

and organic compounds [3-12]. Shonbein [13] put forward the hypothesis of participation of

free charged oxygen atoms (‘‘ozone’’ O and ‘‘antozone’’ Oþ) in oxidation. He considered the oxygen of air as a monoatomic molecule, which can be in passive ‘‘Oo’’ and active (O and Oþ) forms and proposed the following general scheme of oxidation:

Aþ 2Oo ! AþO þOþ AþO ! AO (ozonide)

H2OþOþ ! H2O2 (antozonide)

This scheme faced with a few contradictions. It was yet known at that time that an oxygen

molecule consists of two oxygen atoms. The study of the ozone molecule showed that it

includes more than two oxygen atoms. And, at last, Engler and Nasse [14] proved that gas

‘‘antozone’’ in Shonbein’s experiment was nothing but vapors of the formed hydrogen

peroxide. The proposed scheme with the participation of hypothetical polarized oxygen

atoms (‘‘ozone’’ and ‘‘antozone’’) in oxidation appeared false. However, its background,

namely, the facts of active intermediate formation in oxidation were very important for the

future development of the theory of oxidation.