Atoms bonding within polyatomic ions

Force within units Covalent bond within polyatomic ion Atomic forces between subatomic particles Atomic forces between subatomic particles Covalent bond... 

The bonding between the atoms within polyatomic ions is just like the bonding within molecular compounds (Section 5.3), but the group of atoms has either more or fewer electrons than protons and therefore has an overall charge. Compounds that contain polyatomic ions are ionic, and their formulas are written by the same procedure described for binary ionic compounds. The only difference is that the polyatomic ion formula is enclosed in parentheses when more than one such ion is present. For example, the formula of aluminum nitrate is Al(NOg)g. The compounds are also named in the same manner as binary ionic compounds, with the... 

The polyatomic ions you learned about in Chapter 8 are related to covalent compounds. Although the unit acts as an ion, the atoms within the ion itself are covalently bonded. The structures of these ions can also be represented by Lewis structures. 

Polyatomic ions, such as hydroxide (left), sulfate (center), and oxalate (right), are composed of more than one atom. Electrons are shared between the atoms within the ion, forming covalent bonds, but the ion as a whole has a charge. Thus, polyatomic ions form ionic bonds with other ions to produce ionic compounds. 

Covalent bonds in polyatomic molecules and ions are formed by the overlap of hybrid orbitals, or of hybrid orbitals with unhybridized ones. Therefore, the hybridization bonding scheme is still within the framework of valence bond theory electrons in a molecule are assumed to occupy hybrid orbitals of the individual atoms. 

Polyatomic Ions Covalent Bonds Within Ions Many ionic compounds contain polyatomic ions, which consist of two or more atoms bonded covalently and have a net positive or negative charge. For example, the ionic compound calcium carbonate is an array of polyatomic carbonate anions and monatomic calcium cations attracted to each other. The carbonate ion consists of a carbon atom covalently bonded to three oxygen atoms, and two additional electrons give the ion its 2- charge (Figure 2.15). In many reactions, a polyatomic ion stays together as a unit. 

Ionic crystals are not limited to monatomic ions polyatomic ions—ions consisting of two or more atoms—also form crystal structures. Atoms within a polyatomic ion are held together by covalent bonds (Section 12.3). Figure 12.3 is a model of a calcium carbonate crystal. The formula of a carbonate ion, one of which is circled in Figure 12.3, is The carbon atom is surrounded by three covalently bonded... 

Silicate structures consist of four oxygen atoms bonded to silicon, forming a negatively charged polyatomic anion with a tetrahedral shape. Various metal ions within the structure balance the charge of the compound. 

The compounds described in Example 10-2 are binaty ionic compounds consisting of monatomic cations and monatomic anions. Commonly encountered ternary ionic compounds consist of monatomic and polyatomic ions. Bonding between atoms within the polyatomic ions is covalent. Some ternary ionic compounds are considered later in the chapter. 

A.2.2 Nonpolar Binary Intermetallic Phases. Zintl phases are characterized by the presence of markedly heteropolar bonding between the Zintl ions (electronegative polyatomic clusters) and the more electropositive metal atoms. By contrast, the bonding between heteronuclear atoms within other intermetallic compounds is primarily covalent or metallic. A number of different structure types exist for any given... 

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