THE PROPERTIES OF SOLUTIONS. 



[CH. I. 



Instead of using x cc. of 0-2 N, the amount of the standardised 

 soda that must be employed is 



X X O-2 



CC. 



It is convenient to label the bottle with the factor 



0-2 



0-2 N Hydrochloric acid. This can be prepared from a freshly 

 distilled 20 per cent, solution, and standardised against the standard 

 soda, using methyl red as the indicator. 



Series A. 50 cc. 0-2 M. acid potassium phthalate. 

 x cc. 0-2 N. HC1. 

 Diluted to 200 cc. 



(Thymol blue. 



Indicators recommended 



j Brom-phenol blue. 



Series B. 50 cc. 0-2 M. acid potassium phthalate. 



x cc 0-2 N. NaOH. 

 Diluted to 200 cc. 



Indicators recommended 



Brom-phenol blue. 

 Methyl red. 

 Brom-cresol purple. 



