Chlorine equilibrium constant

The equilibrium constant for this reaction decreases with increase in temperature but the higher temperature is required to achieve a reasonable rate of conversion. Hydrogen chloride is now being produced in increasing quantities as a by-product in organic chlorination reactions and it is economic to re-convert this to chlorine. 

The relative basicities of aromatic hydrocarbons, as represented by the equilibrium constants for their protonation in mixtures of hydrogen fluoride and boron trifluoride, have been measured. The effects of substituents upon these basicities resemble their effects upon the rates of electrophilic substitutions a linear relationship exists between the logarithms of the relative basicities and the logarithms of the relative rate constants for various substitutions, such as chlorination and... 

Chlorination is carried out m a manner similar to brommation and provides a ready route to chlorobenzene and related aryl chlorides Fluormation and lodmation of benzene and other arenes are rarely performed Fluorine is so reactive that its reaction with ben zene is difficult to control lodmation is very slow and has an unfavorable equilibrium constant Syntheses of aryl fluorides and aryl iodides are normally carried out by way of functional group transformations of arylammes these reactions will be described m Chapter 22... 

Sta.bilizers. Cyanuric acid is used to stabilize available chlorine derived from chlorine gas, hypochlorites or chloroisocyanurates against decomposition by sunlight. Cyanuric acid and its chlorinated derivatives form a complex ionic and hydrolytic equilibrium system consisting of ten isocyanurate species. The 12 isocyanurate equilibrium constants have been determined by potentiometric and spectrophotometric techniques (30). Other measurements of two of the equilibrium constants important in swimming-pool water report significantly different and/or less precise results than the above study (41—43). A critical review of these measurements is given in Reference 44. 

In these examples tire entropy change does not vaty widely, and the value of the equilibrium constant is mainly determined by the heat of dissociation. It can be concluded, tlrerefore, that niuogen is one of the most stable diatomic molecules, and tlrat chlorine is tire most stable diatomic halogen molecule. 

It is always important to keep in mind the relative nature of substituent effects. Thus, the effect of the chlorine atoms in the case of trichloroacetic acid is primarily to stabilize the dissociated anion. The acid is more highly dissociated than in the unsubstituted case because there is a more favorable energy difference between the parent acid and the anion. It is the energy differences, not the absolute energies, that determine the equilibrium constant for ionization. As we will discuss more fully in Chapter 4, there are other mechanisms by which substituents affect the energy of reactants and products. The detailed understanding of substituent effects will require that we separate polar effects fiom these other factors. 

Equilibrium constant not known in solution ctystalline form has all chlorines axial. TH-O-acetyl-p-D-xylopyranosyl chloride... 

The large value of the equilibrium constant signifies that the reaction will proceed from left to right almost to completion, i.e. an iron(II) salt is almost completely oxidised by chlorine. 

Again, if we divide the square of the equilibrium constant for hydrogen chloride by that for steam we obtain the equilibrium for the Deacon process of chlorine manufacture ... 

On the analogy of the physicochemical relation, one was led to define a biological Hammett equation which related the equilibrium constant of the drug-receptor complex to the electronic a parameters of the substituents (e.g. chlorine, bromine, methyl, ethyl, hydroxyl, carboxyl, acetyl, etc.) of the drug molecule. Since the equilibrium constant of a drug-receptor complex is reflected by the biological activity, this led to the first extrathermodynamic relationship in QS AR ... 

For this reaction the value of AG° at 800 °C is -66.94 kj. The equilibrium constant for this reaction is 103 35, which is considerably higher than the equilibrium constant for the previous reaction (1021) in which carbon and chlorine are used. 

Two points emerge from this discussion. Simple application of the expression for AG in terms of the equilibrium constant K shows that for the chlorine reaction ... 

The kinetics of chlorination of ethylene, allyl chloride, 3,4-dichlorobutene, 2,3-dichlo-ropropene, and 1,2-dichloroethylene in 1,2-dichloroethane have been investigated in the presence of BU4NCI. The mathematical treatment of the results was performed with due regard to the equilibrium constants of the formation of complexes between CI2 and CP. For all the substrates at 256K, the introduction of CP into the system has been found to result in an increase in the rate of the addition. The reaction turned out to be of first order with respect to both the substrate and the salt and second order with respect to chlorine. As expected, the dependence of the reaction rate on the substiments at the double bond is compatible with the electrophilic addition, initiated by electrophilic chlorine."... 

When heated at elevated temperatures, it decomposes to carhon monoxide and chlorine. The equilibrium constant, Kc at 360°C for the reaction... 

Fluorine chemistry in the stratosphere was also considered and it was concluded that ozone depletion by chlorine was > 104 more efficient than that by fluorine (Rowland and Molina, 1975 Stolarksi and Rundel, 1975). Since then, the kinetics of reaction of F atoms with 02 to form the F02 radical and its thermal decomposition have been measured (e.g., see Pagsberg et al., 1987 Lyman and Holland, 1988 Ellerman et al., 1994 and review in DeMore et al., 1997). The equilibrium constant for the F-F02 system... 

Chlorine, when dissolved in water, undergoes rapid disproportionation (i.e., it oxidizes and reduces itself simultaneously) to hypochlorous acid and hydrochloric acid, with an equilibrium constant of 5 x 10 4 mol2 L 2 ... 

Since the equilibrium constant of reaction 15.19 is 0.93, purple solid iodine is significantly more soluble in aqueous iodide solutions than in pure water. For dilute solutions, however, this can be ignored, as can a similar reaction involving chlorine and chloride in connection with reaction 15.7. Finally, we should remind ourselves that we have assumed that all the activity coefficients are unity (although here again the discrepancy so introduced can be ignored for simplicity). 

Chemical Properties. The chemistry of sulfuryl chloride has been reviewed (170,172,195). It is stable at room temperature but readily dissociates to sulfur dioxide and chlorine when heated. The equilibrium constant has the following values (194) ... 

Chlorine Water and Its Properties. 1. Saturate 5-10 ml of distilled water with chlorine. Note the colour and odour (carefullyl) of the solution obtained. What substances are present in chlorine water Write the equation of the reaction and its equilibrium constant. Test how the obtained chlorine water affects an indigo solution and coloured fabric. What is observed What substance has a bleaching effect ... 

Tables of AG° values for formation of particular compounds (at various temperatures and states) from the elements are available in handbooks and the literature. With these, we can calculate equilibrium constants quite accurately. For example, handbooks give the following data, which are useful for methane chlorination ...

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