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How to determine the purity of nitric acid?

Our company were supplied with nitric acid. My problem is how to determine if the purity of the delivered nitric acid is really pure. The only method that I can do here is by titration, but I do not know how to conduct. Thank You!

Hazel L. Abarado
painting - Cebu City, Philippines
2006

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There have been a few recent letters describing titration methods for passivation tanks - these could be used by you as well. My question is: Why? If you are buying from a reputable supply house and you don't trust them, you've no reason to trust your titration chemicals either. If you aren't buying from a reputable supply house (except for your titration chemicals)... then I guess it makes sense.

Either way, given the fact that titrations are not the most exact way to take a measurement, if the purity is critical I suggest sending a sample to a lab for testing.

Good luck!

Jim Gorsich
Compton, California, USA
2006

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Iha,
You can try 5 ml sample, add 50 ml 4% ammonium oxalate, plus methyl red ⇦this on eBay & Amazon [affil links] indicator, titrate to yellow end point with 1.0 normal NaOH ...calculation is-volume of titrant multiply by 1.26 and you get %volume of nitric acid, you can also try uv analysis using uv spectrophotometer...good luck..

Teody Delgado
- Manila, Philippines
2006