Monatomic ions naming

Naming of the positive ion depends on whether the cation is monatomic (has one atom). If not, the special names given in Sec. 6.3.2 are used. If the cation is monatomic, the name depends on whether the element forms more than one positive ion in its compounds. For example, sodium forms only one positive ion in all its compounds—NaT Iron forms two positive ions—Fc2r and Fe,+. Cations of elements that form only one type of ion in all their compounds need not be further identified in the name. Thus, Na may simply be called the sodium ion. Cations of metals that occur with two or more different charges must be further identified. Fe(NO,)2 and Fe(NO,)3 occur with Fc2+ and Fe3 ions, respectively. If we just call the ion the iron ion, we will not know which one it is. Therefore, for monatomic cations, we use a Roman numeral in parentheses attached to the name to tell the charge on such ion. (Actually, oxidation numbers are used for this purpose, but if you have... 

Binary ionic compounds are compounds composed of two monatomic ions. These usually are a metallic cation and a nonmetallic anion. When naming these compounds, there are a few rules that need to be followed ... 

We learned in Chapter 5 that some metals always form monatomic ions having one given charge in all their compounds. In this book, we will call this type of ion the constant type. Other metals form monatomic ions with different charges (see Figure 5.11). We will call this type the variable type. There are also some polyatomic cations, but only three of these are important for this course. Thus, the first step in naming a cation is to decide which of these three types it is polyatomic, constant type, or variable type. We name them in different ways. 

The Stock system name—vanadium(II) ion—is easy. To use the classical system, we must know the answers to at least three questions (1) What is the charge on the other monatomic ion of vanadium (2) Is the Latin name for vanadium used in the classical system (3) If the Latin name is used, what is that name The Stock system was invented to make naming easier. 

In Chapter 6, we learned how to name cations. In the Stock system, the charges on monatomic ions were used to distinguish between different ions of the same element. For example, Cu and Cu are named copper ion and copper(ll) ion, respectively. The Roman numeral actually represents the oxidation number, not the charge on the ion. Of course, for monatomic ions, the charge is equal to the oxidation number, and thus we used the charge to determine which Roman numeral to use. By using oxidation numbers, however, we can extend our compound-naming ability to include compounds other than those of monatomic ions. For example, Hg2 is called the mercury(I) ion because the oxidation number of each mercury atom is +1. 

In Chap. 6 we placed Roman numerals at the ends of names of metals to distinguish the charges on monatomic cations. It is really the oxidation number that is in parentheses. This nomenclature system is called the Stock system. For monatomic ions, the oxidation number is equal to the charge. For other cations, again the oxidation number is used in the name. For example, Hg2 + is named mercury(I) ion. Its charge is 24- the oxidation number of each atom is 4-1. Oxidation numbers are also used for other cations, such as dioxovanadium(V) ion, V02". The prefix 0x0- stands for oxygen. Oxidation numbers can be used with nonmetal-nonmetal compounds, as in sulfur(VI) oxide for SO3, but the older system using prefixes (Table 6-2) is still used more often. 

You already know how to name monatomic ions. How do you name polyatomic ions Most polyatomic ions are oxyanions. An oxyanlon is a polyatomic ion composed of an element, usually a nonmetal, bonded to one or more oxygen atoms. Many oxyanions contain the same nonmetal and have the same charges but differ in the number of oxygen atoms. More than one oxyanion exists for some nonmetals, such as nitrogen and sulfur. These ions are easily named using the following conventions. 

If the anion is monatomic, the name of the element is amended by changing the ending to -ide. Note that this is the same ending used for binary nonmetal-nonmetal compounds. All monatomic anions have names ending in -ide, but there are few anions that consist of more than one atom which also end in -ide, the most important of these are the hydroxide ion (OH ) and the cyanide ion (CN ). 

Write formulas that correspond to the following names for monatomic ions (a) phosphide ion, (h) lithium ion, and (c) cohalt(ll) ion. 

Convert between the names and chemical formulas for the monatomic ions. 

Write the name for each of these monatomic ions. 

Compounds Formed from Monatomic Ions Let s first consider how to name binary ionic compounds, those composed of ions of two elements. 

The names and formulas of some common cations are shown in TABLE 2.4 and on the back inside cover of the text. The ions on the left side in Table 2.4 are the monatomic ions that do not have more than one possible charge. Those on the right side are either polyatomic cations or cations with more than one possible charge. The Hg2 ion is unusual because, even though it is a metal ion, it is not monatomic. It is called the mercury(I) ion because it can be thought of as two Hg+ ions bound together. The cations that you will encounter most frequently are shown in boldface. You should learn these cations first. 

The names and formulas of the common anions are listed in TABLE 2.5 and on the back inside cover of the text. Those anions whose names end in -ide are listed on the left portion of Table 2.5, and those whose names end in -ate are listed on the right. The most common of these ions are shown in boldface. You should learn names and formulas of these anions first. The formulas of the ions whose names end with -ite can be derived from those ending in -ate by removing an O atom. Notice the location of the monatomic ions in the periodic table. Those of group 7A always have a 1— charge (F , Cl, Br , and I ), and those of group 6A have a 2— charge (0 and ). 

We write symbols for ions analogously to those for atoms, adding the charge on the species as a superscript to the right of the atomic symbol. For monatomic ions, the number of protons still specifies the element whose symbol we use. Table 2.2 provides some examples of monatomic ions. Notice that the monatomic anions have names ending in -ide, whereas cations simply have ion added to the name of the element. 

The naming convention for monatomic ions is familiar from the discussion of covalent molecules above the name of a monatomic anion is the root of the element name with the suffix -ide added. Thus Cl is chloride, Br is bromide, and so on. We can now name FeCli and FeCb as iron(II) chloride and iron(III) chloride, respectively. 

A monatomic ion has a charge of +2. The nucleus of ARIS the parent atom has a mass number of 55. If the number of neutrons in the nucleus is 1.2 times that of the number of protons, what is the name and symbol of the element ... 

The simplest ions are monatomic. A monatomic ion is an ion formed from a single atom. Table 2.4 lists common monatomic ions of the main-group elements. You may want to look at the table while you read first the rules for predicting the charges on such ions and then the rules for naming the monatomic ions. 

---