الفهرس 
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Abstract
Iodination of acetone was studied in different iodine solvents mainly : alcohols (methyl, ethyl and methylated), dioxan and potassium iodide with and without sulphuric acid catalyst at 25°. The solvents, alcohols and dioxan alone, increased the rate of iodination of acetone in the following order : methylated alcohol>dioxan > absolute ethyl alcohol >methyl alcohol.
10% potassium iodide solvent had no effect on the rate of iodination, i.e. the reaction did not occur.
The effect of concentrations of iodine, sulphuric acid and of acetone on the rate of iodination of acetone was studied at 25°. The rate of iodination of acetone was found to ”be independent of iodine concentrations in the two solvents, alcohol and potassium iodide in the presence of 2.5 x 10 -2M sulphuric acid catalyst, however, the rate of iodination was higher in alcohol solvents than in 10% potassium iodide solvent. In the two men¬tioned solvents the rate constant of iodination was independent of sulphuric acid concentrations at low acid concentrations The rate of iodination was also higher in alpohol solvents than in potassium iodide solvent.
At higher acid concentrations the rate constant of iodination with alcohol solvent was no longer constant hut increased by increasing the acid concentrations. The rate of iodination of acetone was proportional to its con¬centrations and the order of the reaction was first in a est one solution.
The effect of formic acid-ammonium hydroxide mixtures on the rate of iodination of acetone showed that the rate of iodination of acetone varied ”by varying the pH’s of formic acid - ammonium hydroxide mixtures . The rate constant of iodination decreased ”by increasing the pH’s to reach minimum at pH 2.64- then increased ”by increasing the pH’s. The effect of ph’s on the rate of iodination of acetone due to the addition of the ”buffers, hydrochloric acid : potassium hydrogen phthalate (I), phenyl acetic acid s sodium phenyl acetate (II) and bisodium hydrogen phosphate : potassium bihydrogen phosphate (III) was studied at 25°• In these buffers iodination took place in alcohol iodine solvent whereas in potassium iodide solvent the reaction did not occur. The rate constant was slightly increased
by increasing the pH’s. It was higher in the presence of (III) than observed with (I) and (II).
The effect of mild oxidizing agents namely : sodium nitrite, potassium persulphate, copper sulphate and ferric sulphate on the rate of iodination of acetone in the presence of 2.5 x 10 -2M sulphuric acid was studied at 25°. The addition of these oxidizing salts increased the rate of iodination more than that obtained with sulphuric acid alone. The increase was independent of the ionic strength of sodium nitrite or of potassium-persulphate hut the rate constant slightly increased with that of co-g-per sulphate or ferric sulphate.
The effect of addition of cuprous iodide on the rate of iodination of acetone in the presence of sulphuric acid, copper sulphate and/or ferric sulphate was investigated at 25°| The rate of iodination was greatly increased due to the addition of cuprous iodide to the reac¬tion medium containing each of the two previously mentioned salts, in the presence or absence of sulphuric acid and when iodine was dissolved in alcohol. The rate constant was independent of copper sulphate concentration but dependent on that of ferric .sulphate. The rate of iodination was proportional to the cuprous iodide con¬centrations. The reaction of iodination was catalyzed, to a greater extent, by the freshly prepared cuprous iodide than by the unfreshly prepared or used cuprous iodide. The effect of the intervals of time after which the catalyst was used, was studied at 25° in the presence of
2.5 x 10-2M sulphuric acid, copper sulphate and ferric sulphate. The rate of reaction decreased by \ increasing the tine before the catalyst was used.
In all runs, iodine was highly consumed at approxi¬mately the zero time of reaction which was very characteristic of the reaction of iodination of acetone in the presence of cuprous iodide; at a later stage of the reaction the consumption of iodine was slow and regular. The order of iodination of acetone was half with respect to cuprous iodide concentrations. Detailed reaction mechanisms. were suggested and the kinetic rate equation in the presence of cuprous iodide was deduced to be represented by.
other metal halides mainly : cuprous chloride, cupric chloride, silver iodide and lead iodide were investigated in iodination of acetone under the same conditions adopted in the case of cuprous iodide. Cuprous chloride was found to be more active than cuprous iodide in iodinat¬ion of acetone, while the other halides, at room temperature , were almost catalytically inactive.
The effect of temperature on the rate of iodination of acetone in the presence of sulphuric acid, copper sulphate, ferric sulphate with and without the studied metal halides was investigated and the averages of the apparent energies of activation were calculated in the temperature interval 25-45 °C The average of the apparent energies of activation of iodination of acetone catalyzed by sul¬phuric acid alone and sulphuric acid and cuprous iodide were almost the same, 19.94- end 20.25 Kcal./mole, respectively. The average of the apparent energies of activation of the reaction in the presence of copper sul¬phate and/or ferric sulphate, which corresponds to the catalytic action of the solvating effect were higher than that of the acid catalyzed reaction and were calculated to ”be 24»67 and 30.16 Kcal./mole, respectively. Iodination of acetone was catalyzed by cuprous iodide at low apparent energy of activation which was found to he 5.712 Kcal./mole.
Cuprous chloride, alone, catalyzed the reaction at a higher apparent energy of activation (13.21 Kcal./mole) than that obtained with presence of cuprous iodide, but at lower apparent energy of activation0 in comparison with that obtained when using sulphurio acid, copper sulphate and ferric sulphate. At higher temperatures the following
metal halides : cupric chloride, silver iodide and lead iodide may slightly catalyze the reaction with apparent energies of activation similar to those of cuprous chloride when was used alone or with sulphuric acid, copper sulphate and/or ferric sulphate,
A similarity between lead iodide and cuprous iodide was observed when each catalyst was used alone; the average of the apparent energy of activation was calculated to be 5.71 kcal./mole.