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Information to everyone on Hydrochloric acid - What is it

Hydrochloric acid is a solution of hydroden chloride gas in water. In general you can dissolve the gas, at atmospheric pressure, to about 36.5%, by weight. People routinely use the term "HCL" to mean the anhydrous gas, as well the aqueous solution. Much of the anhydrous hydrogen chloride used comes as a byproduct of chemical manufacturing using chlorine. Aqueous HCl is produced by dissolving the anhydrous gas in water; This releases a LOT of heat. Often, the same process that produces the anhydrous HCl can or does produce the aqueous acid directly by scrubbing a process vent stream with water. You cannot make aqueous HCl by mixing together 2 other aqueous products, and in fact in water, there really is no HCl at all, only H+ and CL- ions. Chlorine dissolved in water makes a little aqueous HCL, and another species called hypochlorous acid. If you add caustic to this solution, you get hypochlorite, sodium hypochlorite - the chemical name for bleach.

Hope this helps.

Kim Kaiser
Solution Recovery Inc - Ann Arbor, Michigan, USA
2005

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Hi

For some more info on HCl ... go to the archives on the first page of fin.com and hit # 12044 ... a somewhat humorous reply in part ...

Freeman Newton [deceased]
(It is our sad duty to advise that Freeman passed away
April 21, 2012. R.I.P. old friend).
2005