4.24" Mr. Detmer on Bleaching Salts. 



gen and one of soda; but it is equally consistent with Balard's 

 theory that the salt is a mixture of single equivalents of chlo- 

 ride of sodium and hypochlorite of soda. To determine the 

 quantity of chlorine which water dissolves, a stream of the gas 

 was sent through water at 59° for five hours. One hundred 

 grammes of water were found to take up 0*663 gramme of 

 chlorine; or 200 cubic inches of water dissolved 207 cubic 

 inches of gas. The chlorine was estimated by converting it 

 into hydrochloric acid by the addition of a few drops of am- 

 monia, slightly acidulating afterwards by nitric acid, and pre- 

 cipitating by nitrate of silver. A solution of 2"58 chloride 

 of potassium in 38*96 water was found to dissolve less chlo- 

 rine than pure water, in the proportion of 180 to 257. Chlo- 

 rine gas being allowed to stream through a solution of 9"245 

 grammes carbonate of potash in 96'495 grammes of water, till 

 saturation, the solution lost all its carbonic acid and look up 

 6*631 grammes of chlorine. Here 1 eq. of potash = 590 has 

 taken up 656 chlorine, which is very nearly li eq. of chlorine 

 = 663. But when the quantity of free chlorine in the liquid 

 is deducted, the latter is found to contain only 1-34 equivalents 

 of chlorine to 1 eq. of potash. In two other experiments, in 

 which the liquid was agiiated with air after being saturated 

 with chlorine, to allow the excess of gas to escape, there were 

 found to 1 eq. of potash 1*44? and r4'3 equivalents of chlorine. 

 The carbonate of potash, therefore, without doubt, takes up 

 more than a single equivalent of chlorine. But the quantity 

 of chlorine combined with the potash is still greatly short of 

 two equivalents, the proportion required by M. Millon's 

 theory ; the peroxide of potassium containing two oxygen to 

 one potash, or K O3. The conclusion therefore is inadmissi- 

 ble, that the chloride of potash is analogous in constitution to 

 the peroxide of potassium. 



It remains to account for the property which potash is 

 found to possess of taking up more chlorine than is necessary 

 to convert it into chloride of potassium and hypochlorite of 

 potash. On transmitting chlorine through carbonate of pot- 

 ash, a stage in the absorption is very observable, at which the 

 liquid becomes all at once of a yellow colour. This happens 

 when what remains of the potash is entirely converted into 

 bicarbonate of potash. The suddenness of the appearance of 

 the yellow colour appears to be due to a reaction of the car- 

 bonic acid upon the hypochlorite of potash in solution, by 

 which hypochlorous acid is set free and tinges the liquid. By 

 the continued application of chlorine to the bicarbonate of 

 potash, it is converted into a mixture of chloride of potassium, 

 hypochlorite of potash, and free hypochlorous acid. By the 



