Tetrethylpho&phonium and their Decomposition by Heat. 193 



appearance, and formation of the characteristic double salt 

 with iodide of zinc. There appeared to be present along 

 with the phosphine oxide some substance boiling at a higher 

 temperature than 245° C, but we did not succeed in isolating 

 it in a -fit state for examination. 



The triethylphosphine was identified in the hydrochloric 

 acid extract of the first fraction (of the original distillate) by 

 the addition of potash in excess, which at once caused the 

 separation of an oily layer. This had the odour of the phos- 

 phine, and when warmed in air inflamed. On mixing a 

 portion with iodide of ethyl, heat was developed, and a crys- 

 talline compound formed, which analysis showed was iodide 

 of tetrethylphosphonium. 



0'501 grm. required 18*2 cub. centims. 



decinormal nitrate of silver solution = 



0-23114 iodine =46*13 per cent. 



Calculated for (C 2 H 5 ) 4 PI =46*35 per cent. 



In another experiment 10 grms. of the acetate gave, when 

 similarly heated, a distillate composed of 6*5 grms. oxide of 

 triethylphosphine, half a gramme of ketone, and 1 — 1*2 grm. 

 of triethylphosphine, together with 370 cub. centims. of gas, 

 which consisted of nearly equal volumes of carbonic anhy- 

 dride (90 cub. centims.), an olefine (100 cub. centims.), and 

 a paraffin (110 cub. centims.) ; the remaining (70 cub. 

 centims.) gas being the air displaced from the condensing 

 apparatus. 



In order to ascertain which member of the paraffin series 

 the hydrocarbon was which was not absorbable by bromine, 

 some of the acetate was heated in an apparatus filled with 

 pure carbonic anhydride. The gases evolved during the dis- 

 tillation were therefore free from air ; and by subsequent 

 treatment with bromine and caustic potash successively, all 

 the carbonic anhydride and olefine were absorbed, leaving any 

 hydrocarbon of the C n H 2n+2 series. The gas which remained 

 after this treatment burnt with a faintly luminous flame, 

 and a rough analysis gave the following results : — 



I. II. 



cub. cent. cub. cent. 



Gas taken 5"6 11*5 



Oxygen and gas 39*0 44*0 



Oxygen, gas, and air none 11*4* 



After explosion 33*0 445 



Alter addition of caustic potash . 27*0 32 5 

 Phil. Mag. 8. 5. Vol. 22. No. 135. August 1886. O 



