Cations multiple-cation metals

Multiple-cation metals are those that form ions of two or more charges. Most of the transition metals are of this type. Iron, a typical transition metal, can form ions with both a 2+ and 3+ charge, Fe2+ and Fe3+. 

Naming Compounds Involving Multiple-Cation Metals... 

Several Multiple-Cation Metals and Their Names ... 

Use the Stock method to name these ionic compounds involving multiple-cation metals. 

Williams G, D silva C (1994) Field-based heavy metal analyser for the simultaneous determination of multiple cations on-site. Analyst (London) 119 2337-2341... 

Inner-sphere complexes are relatively stable in comparison to outer-sphere complexes under equivalent solution conditions (i.e. pH, ionic strength), and in a competitive situation will tend to displace less stable adsorbates. This is a fundamental property of coordination reactions, and explains the observed trends in metal uptake preference observed in lichen studies (Puckett et al., 1973). Metal sorption results previously attributed to ion exchange reactions are more precisely described as resulting from competitive surface complexation reactions involving multiple cation types. Strictly speaking, each metal adsorption reaction can be described using a discrete mass law relation, such as... 

A compound containing a metal that forms multiple cations must have a Roman numeral in its name. 

Ionic compounds that contain polyatomic ions are named in the same way used to name binary ionic compounds. Attention must be paid as to whether the cation is a metal that forms a single cation or multiple cations, and the name of the polyatomic ion is that given in the table. Note how these six ionic compounds are named ... 

Fe2(S04)3 This compound contains a multiple-cation transition metal, and the charge on the cation must be determined to write a correct name. There are three sulfate ions in parentheses, giving a total negative charge of 6- (3x2- = 6-). The two iron ions then must be iron(III) ions, Fe3+ (2x3+ = 6+), to balance the negative charge of the sulfate ions. The systematic name of the compound is iron(III) sulfate. 

The heavy metals are affected by the various geochemical processes due to change in the soil pH as presented in Parts I, II, and IV. The sorption and desorption processes of coexisting multiple metals is quite complicated. Some of the heavy metals are tightly held than the others. If cationic and anionic metals exist, the sorption behavior of them can be quite the opposite. Therefore, the extent of transport of multiple metals depends on their aqueous concentrations and ionic mobilities. In general, the applied electric field is distributed among the multiple metals, thereby resulting in lower transport of a metal in the mixture as compared with the transport... 

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