Ionic solids containing

Similar relationships hold for ionic solids containing polyatomic ions (Table 2.2) or transition metal cations (Figure 4.2). 

A salt is an ionic solid containing a cation other than H+ and an anion other than OH or O2-. When a salt such as NaCl, K2CO3, or A1(N03)3 dissolves in water, the cation and anion separate from one another. 

Salt An ionic solid containing any cation other than H+ and any anion other than OH" or O2-, 372 carboxylic acid, 595 pH, 373-374... 

The molecules (or atoms, for noble gases) of a molecular solid are held In place by the types of forces already discussed In this chapter dispersion forces, dipolar interactions, and/or hydrogen bonds. The atoms of a metallic solid are held in place by the delocalized bonding described in Section 10-. A network solid contains an array of covalent bonds linking every atom to its neighbors. An ionic solid contains cations and anions, attracted to one another by electrical forces as described in Section 8-. 

As described in Chapter 8, ionic solids contain cations and anions strongly attracted to each other by electrical forces. These forces act between ions rather than between molecules. Ionic solids must be electrically neutral, so their stoichiometries are determined by the charges carried by the positive and negative ions. 

Suppose that an ionic solid contains charged cation vacancies such as NaCl containing Na+ vacancies. Find a relationship, comparable to Eq. 3.50, between the cation tracer self-diffusion coefficient, Dcatlon, and the electrical conductivity, p, due to voltage-induced motion of the cations. 

The superoxides are ionic solids containing the superoxide, Oj. Superoxides of all of the alkali metals have been prepared. Alkaline-earth metals, cadmium, and zinc all form superoxides, but these have been observed only in mixtures with the corresponding peroxides. The tendency to form superoxides in the alkali metal series increases with increasing size of the metal ion. 

Ionic solids contain ions held together by ionic bonds. These solids are typically hard and have high melting points. They are often soluble in water, but insoluble in organic solvents. They do not conduct electricity in the solid state, but do so both in aqueous solutions and in pure molten form. (Use a solid like calcium sulfate as an ionic solid, which is not soluble in water.)... 

Notice that the names of the three classes come from the components of the solid. An ionic solid contains ions, a molecular solid contains molecules, and an atomic solid contains atoms. Examples of the three types of solids are shown below. 

Compounds made up of a metal and a nonmetal tend to be ionic substances. For example, most metal oxides and halides are ionic solids. To illustrate, the reaction between nickel metal and oxygen produces nickel oxide, an ionic solid containing Ni and 0 ions ... 

Again the inference is that conductivity is due to the presence of ions, which are present in the solid state. Evidence that ionic solids contain ions is derived from X-ray diffraction studies and calculations involving lattice energies. 

As mentioned earlier, both tin and lead exhibit the +2 and +4 oxidation states. The charge densities of these ions are shown in Table 21.10. The charge density of Sn is such that many of the compounds containing tin in the +2 oxidation state are covalent however, a few ionic solids containing the Sn ion are known. Lead (II) exists in many ionic solids. When the metals are in the +4 oxidation state, they form covalent bonds, not ionic bonds, because these Sn and Pb " " have very large charge densities and draw electron density from surrounding anions toward themselves. 

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