Group oxidation states

The chemistry of hafnium has not received the same attention as that of titanium or zirconium, but it is clear that its behaviour follows that of zirconium very closely indeed with only minor differences in such properties as solubility and volatility being apparent in most of their compounds. The most important oxidation state in the chemistry of these elements is the group oxidation state of +4. This is too high to be ionic, but zirconium and hafnium, being larger, have oxides which are more basic than that of titanium and give rise to a more extensive and less-hydrolysed aqueous chemistry. In this oxidation state, particularly in the case of the dioxide and tetrachloride, titanium shows many similarities with tin which is of much the same size. A large... 

The group oxidation state of +5 is too high to allow the formation of simple ionic salts even for Nb and Ta, and in lower oxidation states the higher sublimation energies of these heavier metals, coupled with their ease of oxidation, again militates against the formation of simple salts of the oxoacids. As a consequence the only simple oxoanion salts are the sulfates of vanadium in the oxidation states +3 and +2. These can be crystallized from aqueous solutions as hydrates and are both strongly... 

For the heavier congenors, tungsten in the group oxidation state is much more stable to reduction, and it is apparently the last element in the third transition series in which all the 5d electrons participate in metal bonding. 

In moving across the transition series, iron is the first element which fails to attain its group oxidation state (-1-8). The highest oxidation state known (so far) is 4-6 in [Fe04] and even this is extremely easily reduced. On the... 

Group (oxidation state of nitrogen) Group (oxidation state of nitrogen)... 

Krikorian, S.E. 1988. Methodology for quantifying functional group oxidation state levels and for analyzing organic reactions for oxidation-reduction behavior. Am. J. Pharm. Educ. 52, 177-180. 

In each series, the earlier elements can achieve group oxidation state corresponding formally to ions with a noble gas configuration... 

Oxidation States Compounds are formed with elements in the group oxidation state up to Mn, higher states being found mostly with oxides and fluorides. Lower oxidation states are more stable for later elements. Many mixed-valency and non-stoichiometry compounds are known. 

From the table we can see that elements early in series form compounds up to the group oxidation state, for example, II02, VF5 and Cr03. With increasing group number the higher oxidation states become... 

Their chemistry is predominantly that of species in the group oxidation state... 

Note that the group oxidation state is only achieved in the early part of the transition block... 

Finally, in terms of oxidation state formalisms subvalent compounds are often considered to be those for which 0 < Nok < m (where m is the group oxidation state), but in some cases it is also relevant to consider compounds for which Nox < 0. 

In addition to the maximum values attainable, the variety of oxidation states for which compounds can be isolated is of importance. Among the first-row oxides, scandium in Group 3 and zinc in Group 12 appear in only the group oxidation state. In the second and third row, zirconium... 

It is not yet possible to predict the relative stabilities of the 1 and 3 states. In fact, their relative stabilities may weU depend strongly on the state of complexation or hydrolytic conditions. On the other hand, element 115 will not show the group oxidation state of + 5. The other properties of the element may be found in Table 5. 

Equally, the oxyacids in lower oxidation states than the group oxidation state may be treated, again with appropriate expansion of the central element octet. 

Electron configuration, 3. Electronegativity 4 Lewis Group Oxidation State, lonic/covalent. structure. 

ChemProp Group Oxidation Number - Inert Gas Core - 8-electron configuration - V-type Diagrams - Group Oxidation State - Variable Valence. Ligands - [M(OH2)6] - Oxyanions. 

Higher oxidation states are more stable than in the 3 d series, and lower ones less common. The group oxidation state is found up to group 8. 4d and 5d elements of early groups are very similar in later groups higher oxidation states occur in the 5d series. 

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