Acid throwing and readily available in many instances. For example, often acid throwers can purchase a liter of concentrated sulfuric acid at motorbike mechanic shops for about 40 U.S. cents. Nitric acid costs around $1.50 per liter and is available for purchase at gold or jewelry shops, as polishers generally use it to purify gold and metals. Hydrochloric acid is also used for polishing jewelry, as well as for making soy sauce, cosmetics, and traditional medicine/amphetamine drugs. Due to such ease of access, many organizations call for a stricter regulation on the acid economy. Specific actions include required licenses for all acid
Phosphorous acid concentrating the solution and precipitations with alcohols, the pure acid can be separated from the salt. Phosphorous acid is a strong acid with a p"K" in the range 1.26–1.3. It is a diprotic acid, the hydrogenphosphite ion, HP(O)(OH) is a moderately strong acid: The conjugate base HP(O)(OH) is called hydrogen phosphite, and the second conjugate base, , is the phosphite ion. (Note that the IUPAC recommendations are hydrogen phosphonate and phosphonate respectively). The hydrogen atom bonded directly to the phosphorus atom is not readily ionizable. Chemistry examinations often test students' appreciation of the fact that "not" all three hydrogen atoms