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Can a pH 1.0 buffer be made of HCl and nothing else?

Q. I have a question about buffers. I am looking to evaluate a new supplier for a pH 1.0 buffer used to calibrate a pH meter. I have found two suppliers that make it with just hydrochloric acid. Every thing I find in my reference book is that a buffer is always a two component system in this case an acid and a salt. Can you use a solution of just hydrochloric acid to calibrate a pH meter?

Linda

Linda Croft
chem lab tech - Endicott, New York
February 15, 2012

Consider it to be a standard rather than a buffer. It works without a second component mainly because it is highly ionized and quite strong. With proper use, it works well.

James Watts
- Navarre, Florida
First of two simultaneous responses -- February 16, 2012

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Every formulation I've seen includes KCl, too. I think this might contribute to a more stable probe response.

Dave Wichern
Consultant - The Bronx, New York
Second of two simultaneous responses -- February 16, 2012

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February 17, 2012

Good day Linda.
You are indeed correct about two salts. For ph buffer 1.0 try 50 mls. 0.2 M potassium chloride and 134 mls. 0.2 M hydrochloric acid. Hope this helps.
Regards

Eric Bogner
- Toronto Ontario Canada