Oxidation states of chlorine

Hypochlorites, chlorites, chlorates and perchlorates all represent the same dangers, which are linked to the fact that they are strong oxidants. The danger is not directly linked to the importance of the oxidation state of chlorine atom and this is partly for kinetic reasons. The main factors of the accidents described in the technical literature are not the intrinsic properties of each anion, but rather the frequency with which they are used. So chlorates and perchlorates are more often involved in accidents than hypochlorites and especially chlorites, which are hardly used. Thus the classification below does not provide positive indications about the dangerous properties of each substance mention. ... 

The rules above gave maximum and minimum oxidation numbers, but those might not be the only oxidation numbers or even the most important oxidation numbers for an element. Elements of the last six groups of the periodic table for example may have several oxidation numbers in their compounds, most of which vary from each other in steps of 2. For example, the major oxidation states of chlorine in its compounds are -1, +1, +3, +5, and +7. The transition metals have oxidation numbers that may vary from each other in steps of 1. The inner transition elements mostly form oxidation states of + 3, but the first part of the actinoid series acts more like transition elements and the elements have... 

In the next two compounds, the oxidation state of chlorine is -1 (rule 7) and thus the oxidation state of the metal in each cation must be +1 (rule 2). 

However, the high oxidation state of chlorine (VII) in perchlorate makes it a strong oxidant, which readily reacts with most organic species in violent ways under certain conditions such as high temper-... 

The oxidation state of chlorine is +1. The compound is highly unstable, decomposing to chlorine and oxygen when exposed to light, heat, spark, or under catalytic conditions. It reacts with hot water forming hypochlorous acid ... 

The most economical commercial preparation is high-temperature chlorination of ethene. A useful modification of this process uses hydrogen chloride in place of chlorine. An oxidizing agent is required to raise the oxidation state of chlorine in HC1 to that of Cl2 molecular oxygen is used for this purpose along with cupric salts as catalysts. 

EXAMPLE 4 In HCIO4, the oxidation state of chlorine is +7, conforming with corollary (d). 

In contrast to the well-known +7 oxidation state of chlorine and iodine exhibited by the perchlorates and periodates, attempts to prepare perbromates were, until rather recently, unsuccessful. References to the earlier work are given by Bancroft and Gesser.4... 

The term oxidation state is sometimes used and means the same thing as oxidation number. The oxidation number, or oxidation state, of an element in an ionic compound equals the number of electrons transferred from an atom of the element to form the ion. For example, when sodium and chlorine atoms react, the sodium atom transfers one electron to the chlorine atom, forming Na+ and Cl. Thus, in the compound formed, the oxidation state of sodium is 1 + because one electron is transferred from the sodium atom. The oxidation state of chlorine is 1 —. One electron is transferred, and the negative sign shows that the electron transferred to, not from, the chlorine atom. 

Jl examples of-1, 0, +1 and +5 oxidation states of chlorine and the disproportionation of chlorine and chlorate(l) ions... 

Taube, H. and H. Dodgen. 1949. Application of radioactive chlorine to the study of the mechanisms of reactions involving changes in the oxidation state of chlorine. J. Amer. Chem. Soc. 71 3330-3336. 

What is the oxidation state of chlorine in each of the following substances ... 

Electrons are negjative when an atom gains electrons, it gains one negative charge for each electron gained. For example, in the reduction reaction Cl + e —CC, the oxidation state of chlorine decreases from 0 to 1 as the electron is gained. 

Processes in which the oxidation state of an eiement decreases are reduction processes. Consider the behavior of chlorine in its reaction with sodium. Each chlorine atom accepts an electron and becomes a chloride ion. The oxidation state of chlorine decreases from 0 to —1 for the chloride ion (Rules 1 and 2, Figure 1.l). 

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