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Converting Acid Strength to different units

Mostly we used the concentration as mol or Normality of that acid. I would like to know how to check the strength of the acid base on % w/w? Did we need to refer to certain tables?

Radziah Hashim
- Johor, West Malaysia
2001

What about strength of acid by volume (v/v) ? If this would work for you I will send you the test procedures to determine percentage of acid by volume for sulfuric, hydrochloric, and nitric acids.

Nick Cortese
- Atlanta, Georgia, USA
2001

Nick,

I am interested in v/v calculations and would appreciate looking at a procedure.

Thanks,

S Freeman
- Wallingford, Connecticut
2001

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2001

The CRC Handbook of Chemistry and Physics has tables translating wt% into molarity or normality for common acids (about 10 of them), salts, and bases.

If you are confronted with a solution whose concentration is given in wt% and you can't find the material in a published solution-properties table, you have two options: (a) do an acid-base titration (easy if you are set up for it), and (b) (easy and potentially more accurate) determine the density of the solution in g/l (you need a calibrated volumetric flask or pipet and a good balance, not necessarily analytical). Now you know the weight of 1 liter of solution, and multiplying it by the given wt% gives you the concentration in g/l. Divide by the molecular weight to get the molarity.

Emanuel I. Cooper
- Yorktown Heights, New York, U.S.A.