Halogens, oxidation numbers

The acid strengths and oxidizing abilities of the halogen oxoacids increase with the oxidation number of the halogen. The hypohalous acids, HXO (halogen oxidation number +1), are prepared by direct reaction of the halogen with water. For example, chlorine gas disproportionates in water to produce hypochlorous acid and hydrochloric acid ... 

Oxidation A half-reaction in which there is an increase in oxidation number, 88 chromium, 548 electrolysis and, 498 fluorine, 557 halogens, 557-558 oxoacids, 568-570 oxoanions, 568-570 species strength, 506-507q transition metals, 546t zinc, 86-87... 

In reaction (19) the iodine shown on the left has an oxidation number of zero. After the reaction, some of the iodine atoms have oxidation number +5 and some —1. In other words, the iodine oxidation number has gone both up and down in the reaction. This is an example of selfoxidation-reduction, sometimes called disproportionation. It is a reaction quite typical of, but not at all restricted to, the halogens. 

When several oxidation numbers are found for the same element, they often differ from each other by jumps of one unit. For example, in the case of vanadium the common oxidation numbers form a continuous series from +2 to +3 to +4 to 4-5. Compare this with the halogens (Chapter 19). In the case of chlorine, for example, the common states are —1, +1, 4-3, 4-5, and 4-7 (jumps of two units instead of one unit). 

Valence, 286 Valence electrons, 269 and ionization energies, 269 Vanadium atomic radius, 399 eleciron configuration, 389 oxidation numbers, 391 pentoxide catalyst, 227 properties, 400, 401 van der Waals forces, 301 elements that form molecular crystals using, 301 and molecular shape, 307 and molecular size, 307 and molecular substances, 306 and number of electrons, 306 van der Waals radius, 354 halogens, 354 Vanillin, 345... 

The oxidation number of all the halogens is - 1 unless the halogen is in combination with oxygen or another halogen higher in the group. The oxidation number of fluorine is —1 in all its compounds. 

The interhalogens have properties intermediate between those of the constituent halogens. Nonmetals form covalent halides metals tend to form ionic halides. The oxoacids of chlorine are all oxidizing agents both acidity and oxidizing strength of oxoacids increase as the oxidation number of the halogen increases. 

Identify the oxidation number of the halogen in (a) hypoiodous acid (b) CIO, (c) dichlorine heptoxide ... 

The oxidation number of every halogen atom in its compounds is - 1 except for a chlorine, bromine, or iodine atom combined with oxygen or a halogen atom higher in the periodic table. For example, the chlorine atoms in each of the following compounds have oxidation numbers of -1 ... 

Cl has an oxidation state of - I (rule 7). I has an oxidation number of +3 (rule 1). I is not -1 because it is combined with a halogen higher in the periodic table. 

Because chlorine is a halogen, it has an oxidation number of -1. And because there are 6 chlorines, there is a total charge of -6 for the chlorines. The overall charge is -2, so algebraically, x + (-6) = -2. Solving this yields x = +4. Thus, the charge (or oxidation number) of platinum is +4. 

The halogens form a number of stable oxides, but information on their thermal and photochemical decompositions in the gas phase is limited to two oxides of fluorine and several oxides of chlorine. Little research has been done on the decompositions of bromine, iodine or mixed-halogen oxides. 

The oxidation number of halogens in their compounds is -1 except when combined with another halogen above them on the periodic table, or with oxygen. 

Group VllA atoms (halogens) usually have an oxidation number of -1. 

The oxidation number of iodine in IQ2 is +1. This is unusual, because halogens are usually — 1. However, because chlorine is more electronegative than iodine, we assign Cl as — 1, thereby forcing I to be +1. 

Figure 13.4.4 Classification of H atoms in 4,4-difluorobutanoic acid as defined in the model of Ghose et al. [49,50], The subscript represents hybridization and the superscript is the formal oxidation number. X represents any heteroatom (O, N, S, P, Se, and halogens).

The oxidation number of all the halogens is —1 unless the halogen is in combination with oxygen or... 

Give the most common oxidation number for the following elements (a) the alkali metals (b) oxygen, as found in compounds (c) the halogens. 

The acid strengths and oxidizing abilities of the halogen oxoacids (Table 15.8) increase with the oxidation number of the halogen. The... 

In general, the farther left an element is in the periodic table, the more likely it is that the atom will be "cationlike." Metals, therefore, usually have positive oxidation numbers. The farther right an element is in the periodic table, the more likely it is that the atom will be "anionlike." Nonmetals, such as O, N, and the halogens, usually have negative oxidation numbers. We ll see the reasons for this trend in Sections 63-6.5. 

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