Oxides, Peroxides, and Superoxides

Oxides, Peroxides, and Superoxides.— The electron affinity of has been computed from interaction-potential functions applied to the oxides MO (M = Be, Mg, Ca, Sr, or Ba). The value (728.7 kJ moP ) obtained agrees well with those derived from other methods. 

The Raman spectra of peroxides of alkali, alkaline earth, and some transition metals have been measured. The O—O stretching vibration produces an intense band in the expected frequency region of 750—850 cm . The existence of Be02 was inferred from the observation of a weak band at 815 cm and frequency shifts in the hydrates of alkali-metal and alkaline-earth peroxides were thought to indicate differences of water association. 

Solutions of dicyclohexyl-18 crown 6 in DMSO have been used to prepare pale yellow 0.15 mol P solutions of KO2 which contain the O2 anion in approximately the same concentration. The specificity of the superoxide dismutase enzyme was used to show that the solution did indeed contain the superoxide ion in solution. I hc redox potentials of the superoxide and hydroperoxy free radicals, O2 and HO2, have been measured by the fast reaction technique of pulse radiolysis and kinetic absorption spectrophotometry. A d.t.a. study has shown that, during the heating of LiC104-K02 mixtures containing 30% KO2, a eutectic melt occurred at 100—250 C with the loss of superoxide oxygen. At 250—300 °C the mixture melted with loss of peroxide oxygen and at 360— 500 °C the perchlorate decomposed with the loss of all the perchlorate oxygen. 

Lemesheva and V. Ya, Rosolovskii, Tezisy Dokl. Vses. Soveshch. Khim. Neorg. Perekisnykh Soedin., 1973, 88. 

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AlkaU metals react with oxygen to form oxides, peroxides, and superoxides, depending on the metal. Combustion in air yields the following products ... 

In general, metallic oxides (including peroxides and superoxides) are ionic solids. The Group lA metals combine with oxygen to form three kinds of solid ionic products called oxides, peroxides, and superoxides. Lithium combines with oxygen to form lithium oxide. 

To prevent the formation of oxides, peroxides and superoxides, alkali metals are sometimes stored in an inert atmosphere. Which of the following gases should not be used for lithium Why Ne, Ar, N2, Kr. 

The alkali metal oxides, peroxides and superoxides react with water according to equations 10.11-10.13. One use of KO2 is in breathing masks where it absorbs H2O producing O2 for respiration and KOH, which absorbs exhaled CO2 (reaction 10.14). 

Oxygen is the most abundant element in Earth s crust. It forms compounds with most other elements as oxides, peroxides, and superoxides. Its allotropic form, ozone, is a strong oxidizing agent. Sulfur, the second member of Group 6A, also forms many compounds with metals and nonmetals. Sulfuric acid is the most important industrial chemical in the world. (21.5)... 

Define oxide, peroxide, and superoxide. Give an example of each. 

Potassium superoxide, KO2, can also be used for this purpose. The oxides, peroxides, and superoxides of the alkali metals react with water to form basic solutions. The reaction of an alkali metal oxide with water is an acid-base reaction that produces the alkali metal hydroxide. 

A systematic study of oxygen compounds is generally done in conjunction with the study of the other elements. Thus, the oxides of boron were considered in the discussion of boron chemistry in Chapter 21 the oxides of carbon were also considered there. The survey of the chemistry of the alkali and alkaline earth metals in Chapter 21 provided an opportunity to describe normal oxides, peroxides, and superoxides and the important oxides of sulfur, nitrogen, and phosphorus are discussed in this chapter. 

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