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Phosphoric and sulfuric in one bath

 

I am doing a titration with NaOH 2N [on Amazon] to determine the content of a cleaning bath of phosphoric acid, sulfuric acid, and water. I am having a difficult time in figuring out the calculations. Could anyone please shed some light on the subject? I get two inflections points which one is which?

Thanks,

Thomas Rohrer
- Columbus, Ohio

You could see 3 points from the phosphoric and 1 from the sulfuric. I would make up a solution of phosphoric and titrate it, then make up a sulfuric and titrate it. Then make up a mix of the 2 acids and see where the points fall out. I assume that you are using an autotitrator or one that has a print out. I liked using 1N or .5N [on eBay or Amazon] and even 0.1N [an error occurred while processing this directive] for doing the titrations using a smaller sample to compensate. Just worked better for me. It is not cheaper, just safer.

James Watts
- Navarre, Florida
 

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Perhaps you could make up several test solutions with different concentrations of the two acids, titrate each test solution, and relate the titration volumes to the known concentrations of each acid.

Bill Reynolds [deceased]
consultant metallurgist - Ballarat, Victoria, Australia
We sadly relate the news that Bill passed away on Jan. 29, 2010.