The Chemistry of Oxygen

Navy test pilot in an F-14 jet using an oxygen mask. 

Scientists have become concerned that Freons and nitrogen dioxide are promoting the destruction of the ozone layer (Section 15.9). 

It is hard to overstate the importance of oxygen, the most abundant element in and near the earth s crust. Oxygen is present in the atmosphere as oxygen gas and ozone in soil and rocks in oxide, silicate, and carbonate minerals in the oceans in water and in our bodies in water and in a myriad of molecules. In addition, most of the energy we need to live and run our civilization comes from the exothermic reactions of oxygen with carbon-containing molecules. 

The other form of elemental oxygen is ozone (O3), a molecule that can be represented by the resonance structures 

The oxidizing ability of ozone can be highly detrimental, especially when it is present in the pollution from automobile exhausts (see Section 5.11). 

Ozone exists naturally in the upper atmosphere of the earth. The ozone layer is especially important because it absorbs ultraviolet light and thus acts 

Unless otherwise noted, all art on this page is 0 Cengage Learning 2014. 

Navy test pilot in his F/A-18F Super Ftornet wearing an oxygen mask. 

Polonium was discovered in 1898 by Marie and Pierre Curie in their search for the sources of radioactivity in pitchblende. Polonium has 27 isotopes and is highly toxic and very radioactive. It has been suggested that the isotope °Po, a natural contaminant of tobacco and an a-particle producer (see Section 19.1), might be at least partly responsible for the incidence of cancer in smokers. 

Copyright 2010 Cengage Learning, Inc. AU Rights Reserved. May not be copied, scanned, or duplicated, in whole or in part. 

---

Much of the chemistry of oxygen can be rationalized in terms of its electronic structure (2s 2p ), high electronegativity (3.5) and small size. Thus, oxygen shows many similarities to nitrogen (p. 412) in its covalent chemistry, and its propensity to form H bonds (p. 52) and p double bonds (p. 416), though the anionic chemistry of 0 and OH is much more extensive than for the isoelectronic ions N , and NH2. Simi-... 

The nuclear charge and the electrons it attracts primarily determine the ways in which atoms behave toward other atoms. Mass differences cause only minor chemical effects. Since the isotopes of an element have the same nuclear charge and the same number of electrons per neutral atom, they react in the same ways. Thus we can speak of the chemistry of oxygen without specifying which one of the three stable isotopes is reacting. Only the most precise measurements will indicate the very slight chemical differences among them. 

Figure 3, Standard reduction potentials associated with the chemistry of oxygen values in upper and lower halves of diagram refer to pH 0,0 and pH 7,0 conditions,...

Pickard, R.H. and Kenyon,., Contributions to the chemistry of oxygen compounds. I. The compounds of tertiary phosphine oxides with acids and salts,... 

The chemistry of oxygen can be related to that of carbon and nitrogen... 

As in more recent years, the chemistry of seven-membered ring systems has been dominated by the chemistry of oxygen heterocycles in the form of the marine toxins and, to a lesser extent, the antimalarial artemisinin. Indeed, if it were not for the interest in these systems it would have been a sparse year indeed. For this reason the division of this report will be into just three section, nitrogen, oxygen, and other systems. 

For the chemistry of oxygen radicals and oxygen derived species see Halliwell B, Gutteridge JMC (1989) Free Radicals in Biology and Medicine, 2nd edn. Clarendon, Oxford, p 22... 

J. Hartung, T. Gottwald, K. Spehar, Selectivity in the Chemistry of Oxygen-Centered Radicals—The Formation of Carbon-Oxygen Bonds, Synthesis 2002, 1469—1498. 

Greenwood, N. N., Eamshaw, A. (1997). Chemistry of the Elements (2nd ed.). Oxford Butterworth-Heinemann. Chapter 14 presents an excellent discussion of the chemistry of oxygen. 

Space restrictions mean that the reactivity of multiheteroatom systems or fused systems where both rings are heterocyclic cannot be covered in this section - the reader is referred to the relevant CHEC volumes. Space again dictates that the chemistries of oxygen- and sulfur-containing six-membered heterocycles, and the chemistry of monocyclic six-membered heterocycles with more than one heteroatom, are only briefly indicated alongside the description of pyridine/quinoline/isoquinoline chemistry, but especially where these are not shown by the pyridine prototypes, but again the reader should study the CHEC volumes for a full discussion. The inclusion of an extra heteroatom in a six-membered system exaggerates the effect of the first and so often it is possible to predict properties by extrapolation however, the same is not true for the five-membered systems, so these heterocycles with more than one heteroatom are considered in detail and separately. 

In the 1930s, S. Chapman proposed the following set of reactions to explain the chemistry of oxygen species in the stratosphere ... 

Group VI, the oxygen. group Oxygen and its congeners sulfur and selenium are non-metals, whereas tellurium and polonium are classed as metalloids. The chemistry of oxygen is discussed in Chapter 6, and that of sulfur and its congeners in Chapter 17. 

Here we have to say a few additional words about the role of oxygen in the evolution of Earth s biogeochemical cycling. The paramount importance of oxygen has to be commented on specifically. The chemistry of oxygen suits it uniquely for its biogeochemical role. 

---