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Wilhelm Ostwald’s dilution law is a relationship between the dissociation constant ' and the degree of dissociation ' of a weak electrolyte. The law takes the form Where the square brackets denote concentration, and ' is the total concentration of electrolyte. Concerning conductivity, this results in the following relation: ==Derivation== Consider a binary electrolyte AB which dissociates reversibly into A+ and B− ions. Ostwald noted that the law of mass action can be applied to such systems as dissociating electrolytes. The equilibrium state is represented by the equation: If ' is the fraction of dissociated electrolyte, then ' is the concentration of each ionic species. must, therefore be the fraction of ''undissociated'' electrolyte, and the concentration of same. The dissociation constant may therefore be given as For very weak electrolytes , implying that . This gives the following results; Thus, degree of dissociation of a weak electrolyte is proportional to the inverse square root of the concentration, or the square root of the dilution. The concentration of any one ionic species is given by the root of the product of the dissociation constant and the concentration of the electrolyte. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「law of dilution」の詳細全文を読む スポンサード リンク
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