56 Report of Schimmel § Co. 1921. 



» 

 We tabulate the results of these experiments. 



■ . , weight burnt chlorine 



material 



g. per cent. 



bitter almond oil (own distillate), prussic acid, faint . . . 9.94 none (0.000) 



„ „ „ „ „ „ „ strong . . . 7.99 none (found 0.004) 



„ none (natural 



benzaldehyde) 7.24 none (found 0.001) 



benzaldehyde, artificial 5.77 0.01 



7.01 0.009 



11.8 0.007 



the same benzaldehyde + 1 per cent, chlorine | (as 1.05 1.02 



„ „ - „ + 1 „ „ „ monochloro 1.72 1.03 



,, „ „ +1 „ » n I benzene) 1.98 1.02 



„ „ „ + 0.5 per cent, chlorine 2.16 0.52 



„ „ + 0.5 „ „ „ ..... 2.68 0.51 



„ „ „ +0.1 per cent, chlorine ..... 2.615 0.105 



n V » +0.1 n „ i 4.15 0.108 



„ „ + 0.033 per cent, chlorine .... 9.95 0.039 



benzylacetate 8.02 0.005 



with a little chlorine 3.31 0.029 



Whilst the combustion of the materials of these experiments gave no trouble, we 

 had to make an addition of some 95 per cent, of spirit (alcohol) in the case of an anise 

 aldehyde which had been mixed with 1 per cent, of chlorine. In this case the same 

 quantity (by weight) was used of anise aldehyde and of spirit, and the combustion of 

 0.87 g. of this mixture yielded 0.54 per cent, of chlorine, corresponding to 1.08 per cent, 

 of anise aldehyde free of alcohol. The consumption of normal potash solution may, 

 like the consumption of the silver nitrate solution, be utilised for the estimation of 

 the chlorine contents, since in the experiments made the two values accorded with 

 one another, except in the case of the bitter almond oils containing prussic acid, in 

 which case the consumption of lye was considerably greater than the consumption of 

 the silver nitrate, a difference which is obviously to be traced back to the prussic acid % 



In the course of the last six months we have had repeated opportunities to test 

 benzaldehydes of guaranteed chlorine contents, as well as bitter almond oils, "genuine" 

 and free of chlorine, by the method just described, and we might state, on the strength 

 of the values found, that scarcely a single one of the samples investigated accorded 

 with the statements of the respective suppliers. In some cases the discrepancies were 

 very considerable, and we can only explain them by assuming that only the chlorine of the 

 side chain was taken into consideration in the tests, but not the chlorine of the nucleus. 



. . , quantity used chlorine 



material 



g. per cent. 



benzaldehyde, free of chlorine 7.75 0.025 



„ not more than 0.002 per cent, chlorine . . 4.20 0.015 



„ nearly free of chlorine 3.34 0.036 



„ technical . 4.425 0.122 



„ not over 0.002 per cent, chlorine .... 2.44 0.20 



less than 0.02 „ „ „ .... 2.16 0.40 



„ n 0.02 „ „ „ .... 1.56 1.04 



bitter almond oil, genuine, free of prussic acid .... 6.2 0.035 



7.6 0.054 



') We revert to this point further on. 



n n n 



n . . . • 2.94 0.18 



