Oxygen Compounds of Nonmetals

A similar reaction occurs when an equimolar mixture of NO and NO2 is cooled. Two odd electrons, one from each molecule, pair off to form an N—N bond  

At -20°C, dinitrogen trioxide separates from the mixture as a blue liquid. 

Dimerization occurs when two identical molecules combine. 

N2O5 (dinitrogen pentaoxide) N2O4 (dinitrogen tetraoxide) 

Recall the discussion in Chapter 7 (Sections 1,2, and 3) where the principles of resonance, molecular geometry, and polarity 

Click Coached Problems for a self-study module on structures of nitrogen oxides. 

Smog over New York City. From a distance, you can clearly see die layer of smog containing reddish-brown nitrogen dioxide. 

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D.K. STRAUB, Lewis structures of oxygen compounds of 3p-5p nonmetals. J. Chem. Educ., 72, 889 (1995). 

In the first section of this chapter some of the properties of the elements hydrogen, carbon, nitrogen, phosphorus, arsenic, antimony, bismuth, oxygen, sulfur, selenium, tellurium, fluorine, chlorine, bromine, and iodine are described. The following sections are devoted to some of their compounds with one another, especially the single-bonded normal-valence compounds. Compounds of nonmetals with oxygen are discussed in the following chapter. 

Berzehus (19) further appHed and amplified the nomenclature introduced by Guyton de Morveau and Lavoisier. It was he who divided the elements into metalloids (nonmetals) and metals according to their electrochemical character, and the compounds of oxygen with positive elements (metals) into suboxides, oxides, and peroxides. His division of the acids according to degree of oxidation has been Httie altered. He introduced the terms anhydride and amphoteric and designated the chlorides in a manner similar to that used for the oxides. 

The first compounds to be discussed will be compounds of two nonmetals. These binary compounds are named with the element to the left or below in the periodic table named first. The other element is then named, with its ending changed to -ide and a prefix added to denote the number of atoms of that element present. If one of the elements is to the left and the other below, the one to the left is named first unless that element is oxygen or fluorine, in which case it is named last. The same order of elements is used in writing formulas for these compounds. (The element with the lower electronegativity is usually named first refer to Table 5-1.) The prefixes are presented in Table 6-2. The first six prefixes are the most important to memorize. 

This compound is a compound of two nonmetals. The nitrogen is named first, since it lies to the left of oxygen in the periodic table. Then the oxygen is named, with its ending changed to -ide and a prefix denoting the number of oxygen atoms present. 

Cadmium oxide, CdO, like nickel oxide, also adopts the sodium chloride structure (Fig. 1.14). However, unlike nickel oxide, this compound can be made to contain more metal than oxygen. The defects that cause this metal excess are usually considered to be interstitial Cd atoms or ions. In this case the reaction is one in which the solid formally loses oxygen. Because of the rules of equation writing, this must involve the removal of neutral oxygen atoms. Each oxygen lost results in the loss of a nonmetal site. In order to keep the site ratio correct, a metal site must also be lost, forcing the metal into interstitial sites ... 

Background Many elements combine with oxygen or other nonmetals in various ratios i.e. FeO, Fe203, Fe304. This phenomenon demonstrates the Law of Multiple Proportions. In this experiment, you will analyze the ratios in which lead and chlorine can combine and from the data provided, be able to determine the empirical formulas of the compounds produced. 

Many oxides of nonmetals are gaseous molecular compounds, such as C02, NO, and S03. Most can act as Lewis acids, because the electronegative oxygen atoms withdraw electrons from the central atom, enabling it to act as an electron-pair acceptor. For instance, carbon dioxide can react with the oxides of metals because the oxide ion in the metallic oxide is a strong Lewis base ... 

Although the general term carbide applies to the binary compounds of the element carbon, this term is used in systematic nomenclature only when carbon is the more electronegative of the two elements involved. Thus, C02 is called carbon dioxide and not oxygen carbide since oxygen is more electronegative than carbon. Although carbon forms binary compounds with most of the nonmetals, metalloids, and metals, only a few of the more common members of this class are considered here. 

Boron s chemistry is so different from that of the other elements in this group that it deserves separate discussion. Chemically, boron is a nonmetal in its tendency to form covalent bonds, it shares more similarities with carbon and silicon than with aluminum and the other Group 13 elements. Like carbon, boron forms many hydrides like silicon, it forms oxygen-containing minerals with complex structures (borates). Compounds of boron have been used since ancient times in the preparation of glazes and borosilicate glasses, but the element itself has proven extremely difficult to purify. The pure element has a wide diversity of allotropes (different forms of the pure element), many of which are based on the icosahedral Bj2 unit. 

A ternary compound consists of three elements. Ternary acids (oxoacids) are compounds of hydrogen, oxygen, and (usually) a nonmetal. Nonmetals that exhibit more than one oxidation state form more than one ternary acid. These ternary acids differ in the number of oxygen atoms they contain. The suffixes -ous and -ic following the stem name of the central element indicate lower and higher oxidation states, respectively. One common ternary acid of each nonmetal is (somewhat arbitrarily) designated as the -ic acid. That is, it is named by putting the element stem before the -ic suffix. The common ternary -ic acids are shown in Table 4-16. It is important to learn the names and formulas of these acids, because the names of all other ternary acids and salts are derived from them. There are no common -ic ternary acids for the omitted nonmetals. 

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