TEMPERATURE OF VAPOUR FROM BOILING SALINE SOLUTIONS. 



225 



employed in this case was made by dissolving 220 grams of 

 anhydrous calcium chloride in 400 grams of water and 

 boiled normally at 115° C. 



A maximum difference of 6*1° 0. was obtained. A baro- 

 metric reading confirmed 99*9° O. as the boiling point of 

 the pure solvent. 



In his paper Sakurai mentions that he obtained a very 

 m uch greater elevation of temperature in the vapour arising 

 from the boiling solution, when he passed steam into the flask 

 owing to the fact that there was a greater volume of 

 vapour arising from the solution, and consequently less 

 relative loss of heat by radiation. Steam was admitted in 

 some experiments but made very little difference to the 

 temperature of the vapour. It was thought of interest, 

 however, to see what would result on boiling the solution 

 by steam alone in the absence of the bunsen flame. The 

 figures obtained in such an experiment are given below, 

 and it is to be understood that the operations in the fourth 

 column were carried out immediately following the taking 

 of the readings placed opposite them. The solution used 

 was more dilute than in the previous experiment and boiled 

 at 110*4° C. 



Time. 



Thermometer A. 



° c. 



Thermometer B. 



° C. 



Remarks. 



1-30 



'103*2 



100-2 





1*34 



103*2 



100-2 



Steam admitted. 



1*35 



103*6 



101*0 





1-37 



103-5 



102-0 



Removed flame 



1-39 



103-1 



101*6 



also condenser 



1*42 



102*8 



101*6 



Steam shut off, 



1*44 

 1-51 



102*4 

 102*7 



101*2 

 101/6 



flame and con- 

 denser replaced 



O— December 1, 1920 



