Temperature and the Tension of Vapours. 



13 



The following Table contains the tensions which have been 

 observed by Regnault ; those under B/. being his earlier, and 

 those under K". his later determinations : — 



mo 



a. 



P. 



R'. 



R". 



- 20 



008813 



6727 



67-49 



69-2 



- 10 



009028 



113-33 



113-35 



113-2 







009243 



183-43 



183-34 



182-3 



+ 10 



009458 



286-56 



286-40 



286-5 



20 



009673 



433-38 



433-26 



434-8 



80 



009888 



636-30 



636-33 



637-0 



40 



0-10103 



909-62 



909-59 



913-6 



50 



0-10318 



1269-03 



127112 



12680 



60 



0-10533 



173117 



1728-52 



1730-3 



70 



010748 



2313-84 



2307-81 



2309-5 



80 



010963 



3034-79 



3024-41 



2947-2 



90 



0-11178 



391206 



389805 



38990 



100 



0-11393 



496313 



495081 



4920-4 



110 



0-11608 



6204-54 



6208-37 



6249-0 



120 



011823 



7652-65 



7702-20 





According to calculation, 34°*8 corresponds to a tension of 

 757-831 millims., and 34°*9 to one of 760-547 millims. The 

 boiling-point of ether is consequently 34°*88 C. 



Regnault determined the tension of liquid sulphurous acid 

 between —25° and +65° C. In accordance with his Table we 

 take the tension at 0° = 1165*06, and calculate from this, 



«=0*099180+0-000267T-0-00000034T 2 , 

 P = 0-63019 + lo g (373 + T) + 1Og(273 + T) - 2 - 43616 - 



TO 



a. 



pp. 



P. 



R. 



dd. 



-25 



009229 



28-2 

 27-8 

 270 

 26-4 

 25-6 

 25-2 

 248 

 24-4 

 23-6 

 230 

 22-4 



373-85 



373-79 



-f-0-06 



-20 



0-09370 



479-41 



479-46 



-005 



— 10 



0-09648 



762-49 



762-49 



0-00 







09918 



1165 06 



116506 



000 



+ 10 



010182 



1719-84 



1719-55 



+0-29 



20 



010438 



2461-90 



246205 



-015 



25 



010564 



2915-30 



2915-97 



-0-67 



30 



0-10688 



3429-80 



3431-80 



-200 



40 



0-10932 



4665-80 



4670-23 



-4-43 



50 



0-11168 



6214-30 



6220-01 



-571 



60 



0-11398 



8122-30 



8123-80 



-1-50 



65 



0-11510 



9227-20 



9221-40 



+5-80 



The tension at —10° is 762'49 millims.; at -10°*1 we find 

 it to be 759*02 millims. ; the boiling-point of liquid sulphurous 

 acid is -10°072. 



