PRACTICE XIX 



PREPARATION OF A STANDARD NITRIC ACID SOLUTION 1 



Determine the specific gravity of concentrated nitric acid. By 

 the use of the specific-gravity table calculate the quantity sufficient 

 to make 4 liters of solution of the strength equivalent per cubic centi- 

 meter to the standard potassium hydroxid solution. Dilute this with 

 ammonia-free water to 3.5 liters and titrate two 25-cc. portions of 

 the standard potassium hydroxid with the dilute nitric acid, using 

 phenolphthalein as indicator. Then add sufficient ammonia-free 

 water to make the nitric acid of the same titrating strength as the 

 standard alkali. Mix thoroughly and check by another titration. 



1 To be done by the instructor. 



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