lucky123 - 1-4-2008 at 18:48
How would I use a hydrometer to pehaps determine the concentration of a nitric acid after distillation?
Sauron - 1-4-2008 at 20:19
First of all you need a table that gives densities vs % HNO3.
The ones to keep in your head are d = 1.42 is concentrated HNO3 while from about 1.50 on up is very high strength "fuming" HNO3.
IIRC it gets close to 1.52 when 100%.
Anyway to use a hydrometer of the correct range, probably two of them for 1.40-1.50 and another for 1.50-1.60, you need a hydrometer har which is a
lot like a graduated cylinder but without graduations.
From here it ought to be obvious. The hydrometer floats in the acid and you read the density at the top of the acid.
Then consult your chart (and a thermometer) for %. The thermometer because the chart will be for some standard temperature and there will be a
correction factor for temperature deviation from the norm.
Maybe some kind soul will provide the chart required? No. Well, here's one from the information superhighway.
http://www.efma.org/publications/NitricAcid/Section15.asp
[Edited on 2-4-2008 by Sauron]