Monatomic ions oxidation number

Ans. Rule 2 Uncombincd elements have zero charges, and so the oxidation numbers must add up to 0. Since all the atoms are the same, all the oxidation numbers must be the same—0. Rule 3 Monatomic ions have the oxidation numbers of all the atoms add up to the charge on the ion. Since there is only one atom (monatomic), the oxidation number of that atom must add up to the charge on the ion that is. it is equal to the charge on the ion. 

In a sense, each atom s oxidation number makes a contribution to the overall charge on the species. Note that the oxidation numbers in both HF [(+1) -h (-1) = 0] and NH3 [(—3) + 3(+1) = 0] sum to zero. Because compounds are electrically neutral, the oxidation numbers in any compound will sum to zero. For a polyatomic ion, oxidation numbers must sum to the chaige on the ion. (The oxidation number of a monatomic ion is equal to its chaige.)... 

The concept of oxidation number is used to simplify the electron bookkeeping in redox reactions. For a monatomic ion (e.g., Na+, S2 ), the oxidation number is, quite simply, the charge of the ion (+1, —2). In a molecule or polyatomic ion, the oxidation number of an element is a pseudo-charge obtained in a rather arbitrary way, assigning bonding electrons to the atom with the greater attraction for electrons. 

The oxidation number of an element in a monatomic ion is equal to the charge of that ion. In the ionic compound NaCl, sodium has an oxidation number of +1, chlorine an oxidation number of — 1. The oxidation numbers of aluminum and oxygen in A1203 (Al3+, O2- ions) are +3 and —2, respectively. 

The name of a monatomic cation is the same as the name of the element forming it, with the addition of the word ion, as in sodium ion for Na+. When an element can form more than one kind of cation, such as Cu+ and Cu2+ from copper, we use the oxidation number, the charge of the cation, written as a Roman numeral in parentheses following the name of the element. Thus, Cu+ is a copper(I) ion and Cu2+ is a copper(II) ion. Similarly, Fe2+ is an iron(II) ion and Fe3" is an iron(III) ion. As shown in Fig. C.6, most transition metals form more than one kind of ion so unless we are given other information we need to include the oxidation number in the names of their compounds. 

The name of a monatomic cation is the name of the element plus the word ion for elements that can form more than one type of cation, the oxidation number, a Roman numeral indicating the charge, is included. 

The oxidation number of an element in a monatomic ion is the same as its charge. For example, the oxidation number of magnesium is +2 when it is present as Mg2+ ions, and the oxidation number of chlorine is — 1 when it is present as Cl" ions. The oxidation number of the elemental form of an element is 0 so magnesium metal has oxidation number 0 and chlorine in the form of Cl2 molecules also has oxidation number 0. When magnesium combines with chlorine, the oxidation numbers change as follows ... 

The oxidation number of a monatomic ion in an essentially ionic substance is equal to its electrical charge. 

A number of general features in Table 1-3 is apparent. Complexes may be cationic, neutral or anionic. Ligands may be simple monatomic ions, or larger molecules or ions. Many ligands are found as related neutral and anionic species (for example, water, hydroxide and oxide). Complexes may contain all of the same type of ligand, in which case they are termed homoleptic, or they may contain a variety of ligand types, whereby they are described as heteroleptic. Some ligands such as nitrite or thiocyanate can coordinate to a metal ion in more than one way. This is described as ambidentate behaviour. In such cases, we commonly indicate... 

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... 

The oxidation number of every monatomic ion is equal to its charge. 

Arts. For monatomic ions, the charge is equal to the oxidation number. 

For simple monatomic ions, the oxidation number is equal to the charge on the ion. 

Assign an oxidation number to each of the following atoms or monatomic ions. Explain your reasoning. 

Single-atom (monatomic) ions have an oxidation number equal to their charge. So the oxidation number of Mg (aq ) is +2, and the oxidation number of C aq ) is -1. 

Now we can work out the formula of an ionic compound formed between the monatomic ions of two main-group elements, one a metal and the other a nonmetal. Unless a lower oxidation number is specified (as for the p-block metals), the metal atom loses all its valence electrons, and the nonmetal atom gains enough electrons to complete its valence shell. Then we adjust the numbers of cations and anions so that the resulting compound is electrically neutral. A simple example is calcium chloride. The calcium atoms ([Ar]4s2) each lose two electrons, to form... 

An atom in a monatomic ion has an oxidation number identical to its charge. (Review Section 2.10 to see the charges on some common ions.) For example ... 

An atom in a polyatomic ion or in a molecular compound usually has the same oxidation number it would have if it were a monatomic ion. In the hydroxide ion (OH-), for example, the oxygen atom has an oxidation number of -2, as if it were a monatomic O2- ion, and the hydrogen atom has an oxidation number of +1, as if it were H+. 

Monatomic ions have an oxidation number equal to the charge of the ion. Thus, a sodium ion, Na+, has an oxidation number of +1 that of chlorine in a chloride ion, Cl-, is —1. 

Q Oxidation numbers for monatomic ions are the same as their charges. K+ has an oxidation number of +1, and O2- has an oxidation number of -2. 

We do not really need oxidation numbers when working with compounds of monatomic ions we can use the charges to write formulas, and we can predict the charges from the periodic table or deduce them from the formulas. When working with compounds with covalent bonds and polyatomic ions (which also... 

The oxidation number of a monatomic ion is equal to the charge on the ion. This rule is also a corollary of rule 1. If the sum of all the oxidation numbers is equal to the charge and there is only one oxidation number because there is only one atom, then that oxidation number must equal the charge on the monatomic ion. 

Oxidation numbers are used for covalently bonded atoms like charges are used for monatomic ions. 

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. 

Metals with high oxidation numbers tend to act somewhat like nonmetals. For example, many transition metals form oxoanions, such as permanganate ion, chromate ion, and dichromate ion, in which the metal is covalently bonded to oxygen. The ability to form covalent bonds to oxygen is evidence of these metals more covalent nature. (In their low oxidation states, most metals typically exist in ionic compounds as monatomic cations.) Titanium(lV) chloride is an example of a compound in which the... 

Oxidation numbers (also called oxidation states) are used as a sort of bookkeeping method for keeping track of the electrons in polyatomic ions or compounds that have covalent bonds. (For monatomic ions, the charge on the ions works just as well.) Oxidation number is defined as the number of electrons in a free atom minus the number controlled by that atom in the compound. The control of electrons in a covalent bond is assigned to the more electronegative atom of the bond. Eight simple rules can be used to determine the oxidation number of an element from the formula of its compound or ion (Section 16.1). 

The highest oxidation numbers are associated with covalent bonding. The four oxygen atoms in OSO4 are covalently bonded to the osmium atom, and no ions are formed. For any monatomic ion, 41- is the maximum charge. 

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. 

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