ACTION OF PHOSPHIDE. OF SODIUM ON HALOID ETHERS. 183 
it on cooling in long needles, which are somewhat thick and are perfectly 
colourless. The addition of common salt, and especially of hydrochloric acid, 
to its aqueous solution reduces its solubility in a remarkable manner: in fact, 
it is practically insoluble in the dilute acid, and traces may be detected in 
solution by this means. Chloride of tetrabenzyl-phosphonium crystallises from 
an aqueous solution with two molecules of water of crystallisation. The dried 
salt is readily soluble in alcohol, and the solution on slow evaporation yields 
very beautiful, colourless, rhombic crystals of considerable size and perfect 
symmetry. These consist of the anhydrous compound. The dried salt is also 
easily dissolved by chloroform, and on evaporation, the solution yields large 
colourless crystals, which lose chloroform on exposure to the air, and appear to 
have effloresced. A determination of the loss which a specimen of the salt 
crystallised from chloroform suffered when heated to 100° C. showed that the 
chloride had crystallised with 1 molecule of chloroform. We are not aware 
that “chloroform of crystallisation ” has been noticed before in any substance. 
Chloride of tetrabenzyl-phosphonium fuses at 224° C., and volatilises slowly 
at that temperature apparently unchanged. Heated more strongly it decom- 
poses, yielding solid and liquid products, amongst the former being free 
phosphorus. Boiled with a solution of potash it suffers a change, which we 
shall refer to later (see p. 204). 
The composition of the chloride was determined by estimations of carbon, 
hydrogen, chlorine, phosphorus, and water. The combustion was made with 
chromate of lead and oxide of copper. The chlorine was determined gravi- 
metrically by precipitation as chloride of silver, and the phosphorus by titration 
with uranium solution after the salt had been fused with a mixture of caustic 
potash and nitrate of potassium. 
Analysis of Chloride of Tetrabenzyl-Phosphonium. 
Dried Salt. 
. | ‘294 grm. gave ‘837 carbonic anhydride = ‘177-7 per cent. carbon. 
Ny » °188 water Sar ell e. hydrogen. 
O043° |. » ‘2298 chloride of silver = 82 P- chlorine. 
‘OOZor 5 » by titration = AO LO r. phosphorus. 
Calculated for 
Obtained. (C,H,),PC1. 
Carbon, ; ; : Cet : : : 78:0 
Hydrogen, . : rt : : 6°5 
Chlorine, . ‘ , 8:2 : ; : 8:2 
Phosphorus, : ‘ 66 . : 72 
99°6 : 99°9 
* The hydrogen in this experiment is too high and the carbon too low, probably because the salt 
had not been completely dried. 
