XIX. 



ortho-Nitrophenol : C'eHi (Ofi)(n (.NO2X 



■'(2)- 





Maximum Pressure H 



m mm. mer- 

 cury of 

 0= C. 



in Dynes 



Surface- 

 tension X in 

 Erg pro cm 2. 



Specific 

 gravity rf^o 



Molecular 

 Surface- 

 energy ," in 

 Erg pro cm^. 



52 



70 



90.2 

 108 

 124.3 

 140.1 

 156 



no 



185.7 

 204 



38.0 

 36.6 

 34.8 

 33.1 

 31.2 

 29.5 

 27.5 

 25.6 

 23.0 

 20.7 



1.281 

 1.264 

 1.243 

 1.224 

 1.206 

 1.195 

 1.179 

 1.153 

 1.135 

 1.113 



864.7 

 840.3 

 807.9 

 776.4 

 739.1 

 703.1 

 661.4 

 624.9 

 567.3 

 517.3 



Molecular weight: 139.05. Radius of the Capillary tube: 0.04644cm. 



Depth: 0.1 mm. 



The substance melts at 45° C. Under a pressure of 760 mm. it boils at 

 214^.5 C. Above 209^ C. a brown colouring is produced by gradual decom- 

 position. 



The density at 75 C. was: 1.2583; at 100° C: 1.2323; at 125° C: 1.2052. 

 At ^C: d4o=: 1.2832—0.000974(^—50°) -0.00000088 (f-50°)2. 



The temperature-coefficient of.-/ increases evidently with rise of temperature: 

 between 52° and 70° C: 1.35 Erg; between 70° and 90°: 1.60; betweer 90° 

 and 108^ C : 1.77; between 108 and 140° C: 1.84; between 140° and 170 C: 

 2.61; and between 170° and 204° C: about 3.20 Erg pro degree. Probably a 

 gradual decomposition of the substance occurs here, causing this increase of 

 ^ at higher temperatures. 



Molecular weight: 139.05. Radius of the Capillary tube: 0.01644cm 



Depth: 0.1 mm. 



The carefully purified substance melts at 96^ C. 



The density at 100° C was: 1.2797; at 125° C: 1.2588; at 150° C- 12359 

 At P C: ^40= 1.2797- 0.000716 (/— 100 ) - 0.0000016 (/-100°)2- 



The temperature-coefficient of ," increases rapidly with rise of temperature- 

 between 110° and 140 C. it is: about 0.50 Erg; between 140° and 155° C ■ 

 1.00; between 155° and 170^ C: 141; between 170° and 186° C: 1.97- between 

 186^ and 20r C: 2.61°; and between 201° and 218' C. : 3.1 Erg pro degree. 

 It is rather probable, that this fact is connected with a gradual decomposition 

 of the substance. 



