1876.] 



Specific Volumes of Liquids. 



287 



The specific gravity of phosphoryl trichloride at 107 o, 23 is 1-50987 ; 

 Tience its specific volume = =101-58. 



The specific gravity of this compound at 10°, at 51°, and at its 

 boiling-point has already been determined by H. L. Buff*. The results 

 of his observations, compared with mine for the above temperatures, are 

 given below ; the specific gravities are compared with water at 0°. 



10°. 51°. Boiling-point. 



Buff 1-6937 1-6494 (? 1-6194) 1-5090(110°) 



Thorpe .... 1-6936 1-6181 1-51008 (107°-23) 



The specific volume of phosphoryl trichloride, calculated from Buff's 

 numbers, is 101'6. 



II. Vanadyl Trichloride. 



This compound was prepared by heating vanadium trioxide, obtained 

 by reducing the pentoxide by means of hydrogen gas, in a stream of dry 

 chlorine. I am indebted to Dr. Eoscoe for the pentoxide; it was a 

 portion of the sample employed by him in determining the atomic weight 

 of vanadium, and had been prepared with great care ; it was beautifully 

 crystalline and of a magnificent ruby-red colour f. In order to free the 

 vanadyl trichloride from dissolved chlorine, it was maintained at a tem- 

 perature near its boiling-point for a couple of hours in a current of dry 

 carbon dioxide. The chloride was distilled into the flask in which its 

 boiling-point was to be determined. Therm. Casella 0. The liquid 

 commenced to boil at 127°-2 ; the column rapidly rose to 127°-3, at which 

 point it remained constant. n = 10°, £' = 30°. Bar. 764*5 millims. 

 Correction for scale-error on thermometer — 0°-15. Corrected boiling- 

 point 127°-29. Corrected and reduced boiling-point 127°*19. 



The results obtained with the dilatometer may be represented by the 

 formula 



V=l + 0-000 965 236^+0-000 000 898 26t 2 



+ 0-000 000 003 191 63 1\ 

 by means of which is calculated the following Table, showing the true 

 volumes of vanadyl trichloride for every 10° between 0° and 130° : — 



°c. 



Volume. 



Biff. 



°0. 



Volume. 



Biff. 







100000 





80 



108460 



1154 



10 



100975 



975 



90 



109647 



1187 



20 



101969 



994 



100 



110870 



1223 



30 



102985 



1016 



110 



112129 



1259 



40 



104025 



1040 



120 



113428 



1299 



50 



105091 



1066 



130 



114767 



1339 



60 



106184 



1093 









70 



107306 



1122 



127-19 



1-143867 





Ann. Chem. Pharm. jSuppl. vol. iv. p. 184. 



t Phil, Trans. 1867, p. 1. 



