Acid concentration

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Scdc5515

Member
Joined
Aug 30, 2021
Messages
6
Location
Mesa Arizona
Can anybody tell me how to determine the concentration of the nitric acid that I’ve been producing? I use calcium ammonium nitrate with sulfuric acid and water and distill it. The process is supposed to yield a 68% concentration. The byproduct is simple gypsum which can be washed down the drain. I know there’s some type of math calculation by volume or weight but I don’t know how to do that. I thought using a hydrometer in a given amount of 68% nitric acid that I bought from the store and compared that to what I made. There’s a small difference but I don’t know what the difference in percentage is just by reading the hydrometer.
 

jadedalex

Active member
Joined
Feb 20, 2017
Messages
43
Depends on how exact a reading you need. Check the Laboratory Supply companies. Maybe there is a test kit available...
 

Elemental

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Joined
Sep 17, 2020
Messages
129
Location
Charlottesville, VA
The simple method would be to do a titration with a known amount of sodium hydroxide and an indicator (i.e. phenolphthalein). YouTube has plenty of videos to teach titrations. It’s a common general chemistry lab for students. Let me know if you have any questions about it.
 

Lino1406

Well-known member
Joined
Nov 1, 2007
Messages
2,118
Location
Israel
Simpler, check density with areometer or weighing a known volume. Compare result with HNO3 density tables
 

Geo

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Joined
Mar 1, 2011
Messages
6,827
Location
Decatur,Ala.
You can concentrate nitric acid with fractional distillation. It uses your distillation flask and a fractional distillation column. The column allows water to evaporate out of the flask where the nitric acid is condensed and returned to the flask.
 

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