Rubidium reaction with oxygen

Metals react with nonmetals. These reactions are oxidation-reduction reactions. (See Chapters 4 and 18). Oxidation of the metal occurs in conjunction with reduction of the nonmetal. In most cases, only simple compounds will form. For example, oxygen, 02, reacts with nearly all metals to form oxides (compounds containing O2-). Exceptions are the reaction with sodium where sodium peroxide, Na202, forms and the reaction with potassium, rubidium, and cesium where the superoxides, K02, Rb02, and Cs02 form. 

The alkali earth metals form Group 1 of the periodic table, made up of lithium, sodium, potassium, rubidium, cesium, and francium (not shown in Fig. 1.3). Their name derives from the observation that their addition to water generates an alkaline solution. They are all low density, soft, and extremely reactive metals, which are rarely found in their metallic form. This group has properties which are closer and more alike than any other group of the periodic table. Since they desperately want to lose their solitary outer sphere electron, their reactions with almost any other species (including molecular oxygen) are violent and explosive. 

CHLORURE de VINYLIDENE (French) (75-35-4) Forms explosive mixture with air (-18°F/-28°C). Inhibitors such as the monomethyl ether or hydroquinone must be added to prevent polymerization. Readily forms explosive peroxides with air or contaminants (a white deposit may indicate the presence of explodable peroxides). Violent polymerization from heat or on contact with oxidizers, chlorosulfonic acid, nitric acid, or oleum or under the influence of oxygen, sunlight, copper, or aluminum. Violent reaction with alkali metals (lithium, sodium, potassium, rubidium, cesium, and francium). Incompatible with ozone. May cause an explosive reaction with trifluorochloroethylene above 356°F/180°C, perchlory fluoride above 212°F/100°C. May be corrosive or unstable in the presence of steel. 

Andrews and co-workers have used the matrix reaction between lithium atoms and some inorganic compounds to produce species of spectroscopic interest. Reaction of lithium with molecular oxygen [301] produces, in addition to the molecule Li02, the molecule LiO and a dimer Li2 02. Reaction with nitric oxide produced a nitroxide compound [302], but analysis of the infrared spectrum indicated that in this compound the lithium atom was bound to the oxygen atom (LiON), rather than to the nitrogen atom (LiNO), as would be expected by analogy with the known compounds HNO and RNO. The matrix deposition of lithium and nitrous oxide [303] leads to the formation of LiO and LijO. The other alkali metals have also been reacted in the same way with nitrous oxide [304]. Potassium, rubidium and caesium all led to the formation of the compounds MO and M2O. No sodium oxides were produced when sodium and nitrous oxide were co-deposited. This is to be compared with the mechanism advanced for the sodium-catalysed gas-phase reaction between N2O and CO, where sodium is assumed to react with N2O, (Section 4, ref. 

Cesium reacts with water in ways similar to potassium and rubidium metals. In addition to hydrogen, it forms what is known as superoxides, which are identified with the general formula CsO When these superoxides react with carbon dioxide, they release oxygen gas, which makes this reaction useful for self-contained breathing devices used by firemen and others exposed to toxic environments. 

Alkyllithium compounds as well as polymer-lithium associate not only with themselves but also with other alkalimetal alkyls and alkoxides. In a polymerization initiated with combinations of alkyllithiums and alkalimetal alkoxides, dynamic tautomeric equilibria between carbon-metal bonds and oxygen-metal bonds exist and lead to propagation centers having the characteristics of both metals, usually somewhere in between. This way, one can prepare copolymers of various randomness and various vinyl unsaturation. This reaction is quite general as one can also use sodium, rubidium or cesium compounds to get different effects. 

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