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Chemistry %

Just a quick question, I am an old man. I have made up my solution of sulfuric acid with density 2.18 g/l and my finish solution the density is 0.6 g/l I need to know the % of the sulfuric acid in the finish solution?

Blaise Pascal
Quality controller - Melbourne, Australia
2003

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I see dead people. But this student perhaps deserves an A for his/her creative adaption of a homework question into a story.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
2003

It might not be a student as they would have copied the units verbatim. The case that you presented is a total impossibility as water weighs 1 g/mL and gasses have a density somewhat near the 0.6 g/L that you quote. Come back with the correct units of measurement and I will try to give you a simple way of doing it. Can we assume that you are using distilled water as the other portion of the mixture, or is it alcohol or what?

James Watts
- Navarre, Florida
2003

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Conc sulfuric acid has an s.g. of 1.84 (1.84g/cc); water has and s.g. of 1 (1g/cc). Unless you are using oleum which I very much doubt, your original figure is impossible. The final s.g. is also almost certainly wrong unless you are using a very low s.g. solvent that you are not specifying. Perhaps you should get your density equipment checked or get your figures right before asking impossible questions.

Trevor Crichton
R&D practical scientist
Chesham, Bucks, UK
2003