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Is muriatic acid the same as hydrochloric acid?
Is muriatic acid the same thing as hydrochloric acid?Katherine Young
- Indianapolis, Indiana
Katherine, they are generally the same thing-- muriatic is the common name for industrial, or less pure, grades of hydrochloric acid. Treat either with care.
Yes, with a slight difference: muriatic acid contains a higher amount of contaminants. Many of these are added in order to increase its agressivity. Depending on its quality hydrochloric acid can be considered chemically pure.Alfonso Hernandez
- Aurora, Colorado
Would you know what these added contaminants might be? I always assumed the impurities in muriatic acid were present because it is a lower grade product, and it was not necessary for its application, and too expensive to purify further.
After all, muriatic acid can be used for anything from leaching concrete to pickling mill steel to who knows what else, and it is much less expensive than the chemical or reagent grade.
Falls Township, Pennsylvania
After some research I have found out that there is a difference between "added" impurities and impurities that have been "left there" for economical purposes, as Mr. Pullizzi states on his letter.Alfonso Hernandez
- Aurora, Colorado
April 29, 2011
The truth of the matter is, muriatic acid, made and used primarily for industrial use, contains a lower baumé rating, (equaling to a higher amount of impurities) than what it's derived from, hydrochloric acid, which is made and used primarily for laboratory applications due to it's higher baumé rating, resulting in less impurities. In other words, hydrochloric acid, is of a slightly higher grade than muriatic acid. The Mad ScientistVance Bianchi
- Henderson, Nevada
June 1, 2011
I have read to use nitric acid to etch meteorites and wanted to use Muriatic acid-since I have some. The recipe calls for nitric acid to be mixed with ethanol for etching meteorites. Would it be feasible to use the muriatic acid instead?
- North, Texas, USA
|June 1, 2011|
Muriatic acid is a totally different thing than nitric acid and substitutions are not possible. Nitric acid is an oxidizing acid, muriatic is not. The nital etch, however, can be quite dangerous (explosive, not just corrosive) and I don't think you should engage in working with these materials unless you either are a chemist with a good understanding of them or you have received hands-on training in their use, including haz-mat training. Good luck.
Ted Mooney, P.E. RET
Pine Beach, New Jersey