Nonmetals Oxygen

In the foregoing discussion, it is clear that many acids contain a nonmetal, oxygen, and hydrogen. This suggests that one way to prepare an acid might be to carry out a reaction of the oxide of a nonmetal with water. In fact, this is exactly the case, and many acids can be prepared in this way. For example,... 

Aluminum is the third most abundant element found in the Earths crust. It is found in concentrations of 83,200 ppm (parts-per-million) in the crust. Only the nonmetals oxygen and silicon are found in greater abundance. Aluminum oxide (Al Oj) is the fourth most abundant compound found on Earth, with a weight of 69,900 ppm. Another alum-type compound is potassium aluminum sulfate [KA1(S0 )2 12H20]. Although aluminum is not found in its free metalhc state, it is the most widely distributed metal (in compound form) on Earth. Aluminum is also the most abundant element found on the moon. 

Poloninm is a member of the oxygen group of elements and has the electronic confignration [Xe]4f 5d" 6s 6p. In this gronp, there occurs the transition from the typical nonmetals (oxygen and sulphur) to the metalloids (selenium and tellnrinm) and the metal (poloninm). 

The elements of groups 13—16 fall into three categories (Fig. 1.3), the metalloids, the other metals, and the nonmetals. The important biological role of some of the nonmetals, oxygen, nitrogen, phosphorus, sulfur, and selenium together with the halogens, chlorine and iodine, will be discussed in Chapter 18. 

Reactions of O2 with Nonmetals. Oxygen combines with many nonmetak to form mokcuUtr oxides. For example, carbon bums in oxygen to form carbon monoxide or carbon dioxide, depending on the relative amounts of carbon and oxygen. 

Many ionic compounds contain either aluminum (a Group 3A metal) or a metal from Group lA or Group 2A and a nonmetal—oxygen, nitrogen, or a halogen (Group 7A). Write the chemical formulas and names of all the binary compounds that can result from such combinations. 

These elements, the chalcogens (pronounced kal -ke-jens), show the transition from nonmetal (oxygen, O, sulfur, S, and selenium, Se) to metalloid (tellurium, Te) to metal (polouium, Po). Oxygeu occurs as a colorless, odorless gas with O2 molecules. It also has au aUotrope, ozoue, with molecular formula O3. Sulfur is a brittle, yellow solid with molecular formula Sg. Tellurium is a shiuy gray, brittle soUd polouium is a silvery metal. 

In general, oxyacids contain a nonmetal, oxygen, and what other element ... 

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. 

Phosphoms shows a range of oxidation states from —3 to +5 by virtue of its electronic configuration. Elemental P is oxidized easily by nonmetals such as oxygen, sulfur, and halides to form compounds such as 2 5 2 5 reduced upon reaction with metals to generate phosphides. The... 

Nonmetal atoms form negative ions (anions—pronounced AN-i-ons) by gaining electrons. Consider, for example, what happens when atoms of the nonmetals chlorine and oxygen acquire electrons ... 

When a nonmetal forms two oxoanions, the suffix -ate is used for the anion with the larger number of oxygen atoms. The suffix -ite is used for the anion containing fewer oxygen atoms. 

When a nonmetal forms more than two oxoanions, the prefixes per- (largest number of oxygen atoms) and hypo- (fewest oxygen atoms) are used as well... 

In molecules of this type, the terminal atoms are most often halogens (F, Cl, Br, I) in a few molecules, oxygen is a terminal atom. The central atom is a nonmetal in the third,... 

In the past 40 years, compounds have been isolated in which xenon is bonded to several nonmetals (N, C, and Cl) in addition to fluorine and oxygen. In the year 2000, it was reported [Science, Volume 290. page 117) that a compound had been isolated in which a metal atom was bonded to xenon. This compound is a dark red solid stable at temperatures below -40°C it is believed to contain the [AuXe4F+ cation. 

Allotropy is a very common phenomenon shown by metals, metalloids, and nonmetals. In the gaseous or liquid state, allotropes most often differ from one another in molecular formula. Consider, for example, the two allotropes of gaseous oxygen, 02, and ozone, 03. 

The transition metals, unlike those in Groups 1 and 2, typically show several different oxidation numbers in their compounds. This tends to make their redox chemistry more complex (and more colorful). Only in the lower oxidation states (+1, +2, +3) are the transition metals present as cations (e.g., Ag+, Zn2+, Fe3+). In higher oxidation states (+4 to +7) a transition metal is covalently bonded to a nonmetal atom, most often oxygen. 

Table 21.4 lists some of the more important oxoacids of the nonmetals. In all these compounds, the ionizable hydrogen atoms are bonded to oxygen, not to the central nonmetal atom. Dissociation of one or more protons from the oxoacid gives the corresponding oxoan-ion (Figure 21.8, p. 567). 

Trends in acid strength can be explained in terms of molecular structure. In an oxoacid molecule, the hydrogen atom that dissociates is bonded to oxygen, which in turn is bonded to a nonmetal atom, X. The ionization in water of an oxoacid H—O—X can be represented as... 

Strategy The structure can be obtained by removing an oxygen atom from H O, (Figure 21.8). Relative acid strengths can be predicted on the basis of the electronegativity and oxidation number of the central nonmetal atom, following the rules cited above. 

Carbon atoms may be bonded to each other or to other nonmetal atoms, most often hydrogen, a halogen, oxygen, or nitrogen. In most organic compounds—... 

We can often decide whether a substance is an ionic compound or a molecular compound by examining its formula. Binary molecular compounds are typically formed from two nonmetals (such as hydrogen and oxygen, the elements in water). Ionic compounds are typically formed from the combination of a metallic element with nonmetallic elements (such as the combination of potassium with sulfur and oxygen to form potassium sulfate, K2S04). Ionic compounds typically contain one metallic element the principal exceptions are compounds containing the ammonium ion, such as ammonium nitrate, which are ionic even though all the elements present are nonmetallic. 

FIGURE 1.62 The Croup 16A/I elements. From left to right oxygen, sulfur, selenium, and tellurium. Note the trend from nonmetal to metalloid. 

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