In practice sulfuric acid is used with the sodium chlorate, so that the final products are sodium acid sulfate and a mixture of 20 per cent chloroacetone and 80 per cent bromoacetone, according to the reaction: 5(CH₃)₂CO + 4Br + H₂SO₄ + NaClO₃ = 4CH₂BrCOCH₃ + CH₂ClCO CH₃ + NaHSO₄ + 3H₂O. This product is equally as effective as bromoacetone alone and is very much cheaper to manufacture. In general its properties resemble very closely those of bromoacetone. GERMAN MANUFACTURE OF BROMOACETONE AND BROMOMETHYLETHYL KETONE[17] These two products were prepared by identical methods. About two-thirds of the product produced by the factory was prepared from methylethyl ketone which was obtained from the product resulting from the distillation of wood. The method employed was to treat an aqueous solution of potassium or sodium chlorate with acetone or methylethyl ketone, and then add slowly the required amount of bromine. The equation for the reaction in the case of acetone is as follows: CH₃COCH₃ + Br₂ = CH₂BrCOCH₃ + HBr Ten kg.-mols of acetone or methylethyl ketone were used in a single operation. About 10 per cent excess of chlorate over that required to oxidize the hydrobromic acid formed in the reaction was used. The relation between the water and the ketone was in the proportion of 2 parts by weight of the former to 1 part by weight of the latter. For 1 kg.-mol. wt. of the ketone, 10 per cent excess over 1 kg. atomic-weight of bromine was used. [Footnote 17: Norris, J. _Ind. Eng. Chem._, 11, 828 (1919).] The reaction was carried out either in earthenware vessels or in iron kettles lined with earthenware. The kettles were furnished with a stirrer made of wood, and varied in capacity from 4,000 to 5,000 liters. They were set in wooden tanks and cooled by circulating water. The chlorate was first dissolved in the water and then the ketone added. Into this mixture the bromine was allowed to run slowly while the solution was stirred and kept at a temperature of from 30° to 40° C. The time required for the addition of the bromine was about 48 hrs. When the reaction was complete, the oil was drawn off into an iron vessel and stirred with magnesium oxide in the presence of a small amount of water in order to neutralize the free acid. It was then separated and dried with calcium chloride. At this point a sample of the material was taken and tested. The product was distilled to tell how much of it boiled over below 130° when methylethyl ketone had been used. If less than 10 per cent distilled over, the bromination was considered to be satisfactory. If, however, a larger percentage of low boiling material was obtained, the product was submitted to further bromination. The material obtained in this way was found on analysis to contain slightly less than the theoretical amount of monobromoketone.