Charge of cations

The zeolite frameworks are built up of SiO tetraliedra, which are neutral, and AlO tetraliedra, which have a charge of-1. The charge of tire AlO tetraliedra is balanced by tire charges of cations located at various crystallographically defined positions in the zeolite, many of tliem exposed at tire internal surface. The cations are... 

Several metals that are farther removed from the noble gases in the periodic table form positive ions. These include the transition metals in Groups 3 to 12 and the post-transition metals in Groups 13 to 15. The cations formed by these metals typically have charges of +1, +2, or +3 and ordinarily do not have noble-gas structures. We will postpone to Chapter 4 a general discussion of the specific charges of cations formed by these metals. 

Let s try an example. What is the formula of potassium phosphate We can use our method for assigning the charge of cations to predict that potassium will be present as a K+ ion. You should already know that the phosphate ion is PC)43. The difference in charges shows us that it will take three potassium ions to balance the charge on the phosphate ion. Therefore, the formula of potassium phosphate is K3P04. 

Figure 9.2 Formation of an electrical double layer responsible for electroendosmotic flow in an uncoated fused-silica capillary. The negative charges on the surface of the capillary are neutralized by positive charges of cations present in the buffer, which form an electrical layer near the surface of the capillary. When the electric held is apphed, the positive charges migrate toward the negative electrode, generating a bulk flow of the solution contained within the column. Electroosmosis exhibits a flat prohle, in contrast to hydraulic flow, which is parabolic.

M = charge of cation exchanging with cation of charge N. 

Fig. 4.20 Hydration energies as a function of size and charge of cations. [From Philips, C. S. G. Williams, R. J. P. Inorganic Chemistry Clarendon Oxford, 1965. Reproduced with permission.]...

In electrolysis, the cathode is negative, and attracts cations. In a battery, the transfer of charges of cations lo the cathode makes it the positive terminal. 

Adjust HC03" = total electrical charge of cations 1.09 Change kaolinite back into biotite 0.07 ALSi205(0H)4 + 0.42 Mg2+ + 0.14 K+ + 1.09... 

The positive charge of cationic dyes may be either localized or delocalized. In 1, the positive charge is localized on an ammonium group ... 

An ion charged positive is called a cation and an ion charged negative is called an anion. The total charge of cations is of course equal to the total charge of anions in any electrolytic solution which is electrically neutral as a whole. 

The opposite charges of cations and anions attract to form a tightly packed substance of bonded ions called a crystal lattice. 

Anion gap. To maintain electrical neutrality, the sum of the charges of anions in a blood sample must equal the sum of the charges of cations when expressed in molar concentrations. With all units in mmol/L, an anion gap (AG) can be calculated as... 

The association or formation constants of ion pairs are generally less than 10 and increase with the increasing charges of cation and ligand. Summarized here are association constants at 25°C for ion pairs as a function of cation and ligand charge. 

For any chemical reaction system in solution, the charge of anions must be balanced by the charge of cations this is the electroneutrality requirement In the simple H2O—CO2 system with no inputs of bases or acids, the electroneutrahty requirement... 

Avogadro s number unit charge, 4.80 x 10 esu ionic charge of cation and anion -1... 

Davis developed an equation similar to the Vanselow equation from statistical thermodynamics. Electrostatic forces between colloid surfaces and adsorbed cations were calculated for various surface configurations of charge sites. These sites were assumed to be neutralized by individual adsorbed ions. Hence, the model resembles most closely the Helmholtz model of the double layer with the charge of cations on the surface assumed to be just equal to the number of colloid charges. The resultant equation is... 

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