Polyatomic ions names

If the polyatomic ion name ends in -ate, change the ending to -ic if the polyatomic ion name ends in -ite, change the ending to -ous. 

Inorganic compounds are also formed from more than three elements (see Table 6.8). In these cases, one or more of the ions is often a polyatomic ion. Once you have learned to recognize the polyatomic ions, naming these compounds follows the patterns we have already learned. First identify the ions. Name the cations in the order given, and follow them with the names of the anions. Study the following examples ... 

Table 2.2 lists some of the polyatomic ions that you will need to know, along with their names... 

Polyatomic ions, as you have seen (Table 2.2), are given special names. Certain non-metals in Groups 15 to 17 of the periodic table form more than one polyatomic ion containing oxygen (oxoanions). The names of several such oxoanions are shown in Table 2.3. From the entries in the table, you should be able to deduce the following rules ... 

Some elements—particularly the halogens—form more than two kinds of oxoanions. The name of the oxoanion with the smallest number of oxygen atoms is formed by adding the prefix hypo- to the -ite form of the name, as in the hypochlorite ion, CIO-. The oxoanion with the most oxygen atoms is named with the prefix per- added to the -ate form of the name. An example is the perchlorate ion, C104-. The rules for naming polyatomic ions are summarized in Appendix 3A and common examples are listed in Table D.l. 

Step 2 If the compound is an oxoacid, derive the name of the acid from the name of the polyatomic ion that it produces, as in Toolbox D.1. In general,... 

U 1 Name ions, binary inorganic compounds, oxoacids, compounds with common polyatomic ions, and hydrates, and write their formulas (Toolboxes D.l and D.2, Self-Test D.l, and Examples D.l, D.2, and D.3). 

There are many different polyatomic anions, including several that are abundant in nature. Each is a stable chemical species that maintains its stmcture in the solid state and in aqueous solution. Polyatomic anions are treated as distinct units when writing chemical formulas, naming compounds, or drawing molecular pictures. The names, formulas, and charges of the more common polyatomic anions are listed in Table 3-4. You should memorize the common polyatomic ions because they appear regularly throughout this textbook. 

Work from name to formula, using information about polyatomic ions and being careful to build a formula that is electrically neutral. 

There are also some polyatomic ions that end with the letters -ite. S032- and N02 are examples of polyatomic ions with -ite endings. The ion S032- is called a sulfite ion and N02 is a nitrite ion. To name an acid that contains a polyatomic ion that ends in -ite, change the -ite to -ous and add the word acid. Therefore, the name for H2SOs is sulfurous acid and HN02 is nitrous acid. 

Many bases contain the polyatomic ion hydroxide (OH ). To name a base containing this ion, name the metal first, then list the... 

Not all bases contain hydroxide, however. For example, Na2C03 is a base, but its name is sodium carbonate. Baking soda, which has a chemical formula of NaHC03, is also a base. The scientific name for baking soda is sodium hydrogen carbonate (hydrogen carbonate is the name of the polyatomic ion). 

You will also need to learn the names, formulas, and charges of the following polyatomic ions ... 

When naming compounds containing species not on these lists, it may help to find a chemical species on the list from the same family or a polyatomic ion that is similar. 

The presence of a polyatomic ion in a compound requires substituting the name of the polyatomic ion for the name of the cation or anion in a comparable mctal/nonmetal compound. We will use no prefixes. 

From your earlier work, you will recognize the sulfate ion, S04 , as a polyatomic ion. To review the names and formulas of common polyatomic ions, refer to Appendix E, Table E.5. 

Table E.5 Alphabetical Listing of Common Polyatomic Ions Table E.6 Summary of Naming Rules for Ions... 

The names of polyatomic ions may be used directly in compounds that contain... 

Crafting names and formulas for ionic and molecular compounds Handling polyatomic ions Talking about acids... 

When you write a chemical formula that involves polyatomic ions, you treat them just like other ions. You still need to balance charges to form a neutral atom. We re sorry to report that when you re converting from a formula to a name, you can t use any simple rule for naming polyatomic ions. You just have to memorize the entire table of polyatomic ions and their charges. 

When you re tasked with writing the name of a formula containing a polyatomic ion, you follow all the Scime naming rules as listed previously except for one very simple change You don t change the ending of any polyatomic ion. You leave it exactly as it written. 

Lithium nitrate. Because lithium is an alkali metal and the charge of alkali metals in Group I is always -i-l, you don t need to use Roman numerals to indicate the charge of lithium. You simply write lithium and then the name of the polyatomic ion, which is nitrate. You don t change the ending of the polyatomic ion ncime. 

A< Ba(Q02)2.Bcirium is an alkaline ecirth metal (Group IIA) and thus has a chcii e of -1-2. You should recognize chlorite as the name of a polyatomic ion. In fact, any anion name that doesn t end in -ide should scream polyatomic ion to you. As Table 6-1 shows, chlorite is ClOj , which reveals that the chlorite ion has a-1 charge. Two chlorite ions cire necessary to neutralize the -1-2 chcirge of a single barium cation, so the chemical formula is Ba(C102)2-... 

J 1 Oxy-acids Oxy-acids contain hydrogen bonded to a polyatomic ion containing oxygen. To name a binary acid (no oxygen), use the following steps ... 

Is the anion a polyatomic ion If so, you have to recognize it as such and have its name memorized (or easily accessible in a nifty table such as Table 6-1). If the anion isn t a polyatomic ion, you use an -ide ending. 

Identify the anion for each oxy-acid from the polyatomic ion chart in Table 6-1. If the polyatomic ion ends in -ate, change the ending to -ic. If the polyatomic ion ends in -/Ye, change the ending to -ous. Write acid at the end of the name. (Don t begin with hydro- These aren t binary acids.)... 

FeCl2 or FeCl3 compound. Therefore iron must include a Roman numeral to specify which cation is in the compound. Iron (II) chloride is FeCl2 and iron (III) chloride is FeCl3. Two or more atoms may combine to form a polyatomic ion. Common polyatomic ions are listed in Table 1.3. The names of polyatomic ions may be used directly in compounds that contain them. Hence, NaOH is sodium hydroxide, CaC03 is calcium carbonate, and Ba(N03)2 is barium nitrate. 

We first met polyatomic ions and oxoanions in Section C. Many of the most important and common polyatomic anions are the oxoanions (Table D.l). If only one oxoanion of an element is common, its name is formed by adding the suffix -ate to the stem of the name of the element, as in the carbonate ion, C032-. Some elements can form two types of... 

Ionic compounds containing polyatomic ions (Section 2.8) are named in the same way as binary ionic compounds First the cation is identified and then the anion. For example, Ba(N03)2 is called barium nitrate because Ba2+ is the cation and the N03 polyatomic anion has the name nitrate. Unfortunately, there is no systematic way of naming the polyatomic ions themselves, so it s necessary to memorize the names, formulas, and charges of the most common ones listed in Table 2.3. The ammonium ion (NH4+) is the only cation on the list all the others are anions. 

The names and charges of the common polyatomic ions must be memorized. Refer to Table 2.3 if you need help. 

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