12N Hydrochloride - 12N Hydrochloride (Dec/20/2005 )

Hi,

I understand that Normality = n* Molarity and n is the number of protons that are exchanged in a rxn ...but what does it mean when you order in a bottle of Concentrated Hydrochloride and it says 12N? If it depends on the reaction that HCl is involved in, how can they give a standard normality without knowing what it's being used for? I could be totally confused...

Thanks so much!

Normal is the molarity of the released hydrogen ions when the acid dissociates. For HCl, molarity = normality. For sulphuric acid, H2SO4, there are two hydrogens which dissociate, so 1 M sulfuric acid is 2 N sulfuric acid. Extra credit: what is the molarity of a 1 N phosphoric acid solution?

Similar story for bases. 1 N NaOH = 1 M NaOH, but not true in general.