Higher-valent states

Additionally, the ability of H2O2 to oxidize a metal to a higher-valent state, resulting in a more insoluble hydroxide (higher-valent metal hydroxides are more insoluble at a particular pH than the hydroxide of the metal in a lower-valent state) has been pointed out in this study. 

Nitrites decompose at lower temperatures than the corresponding nitrates. The course of decomposition depends on the nature of the salt and the gas phase composition. Nitrites of the more electropositive elements decompose to form the oxide directly by reactions of the type 2 MN02 = M20 + NO +N02, but if the gases are not immediately removed, the nitrite is easily oxidized to the nitrate by N02, if the latter salt is stable at the decomposition temperature. In some cases, particularly the rare-earth nitrites, the first decomposition product is an oxynitrite. According to Addison and Sutton,5 simple nitrites will be stable only if a higher valent-state of the metal is not readily available. Otherwise, decomposition to oxynitrites will occur to achieve the more stable valence of the metal. This view is supported somewhat by the nonexistence of many nitrites of metals in the first two long periods of the periodic table. 

Thus, certain structural features, in particular incorporation of the central atom into a five-membered ring, chelate, macrocyclic and cryptate effects may stabilize the geometry of penta- and hexa-coordinate silicon species. Much of the insight as to which structural features might be expected to stabilize this species comes from studies of species involving higher valent states of other nonmetallic elements of the third row of the periodic table os-so )... 

Halides tend to stabilize the higher valent states of Os and so their chemistry has been described in previous sections. The interconversion of oxidation states in a series... 

Lower-valent organometallic derivatives of Groups V and VI undergo oxidative addition reactions to produce the higher-valent state. These reactions can also be effected with heterocyclic compounds. 

One of the most interesting methods of forming the transition metal-carbon (T-bond is the oxidation of a metal complex from a low to a higher valent state with concomitant metal-carbon bond formation. Both one-and two-electron oxidations have been observed, the latter being the well known oxidative addition reaction. 

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