Sciencemadness Discussion Board

Salt + Citric acid = HCl?

Random - 2-7-2010 at 13:13

http://castboolits.gunloads.com/showthread.php?t=83978

I was reading the page above that says HCl is made with reaction of citric acid and table salt. Is this true? It looks false because citric acid alone would react with zinc.

psychokinetic - 2-7-2010 at 13:18

Acid + Salt = Acid-+Sa + Hlt, but I am still dubious.

Anders Hoveland - 2-7-2010 at 13:41

It all depends on your perspective. Cl- and H+ will be dissolved in the same solution.
Does this mean HCl is made? Not quite, as the solution is still no more acidic than citric acid and you will (almost certainly) not be at boil out HCl. You cannot boil out HCl from NaCl and water, for instance.

However, possibly fusing molten NaCl and citric acid together, but I think the citric acid will likely decompose before you get any HCl.

You can, however, boil out HCl from NaCl and H3PO4 solution, and H3PO4 is not a strong acid, so I would not "entirely" discount what you heard. I think phosphoric acid is much stronger than citric though, so can more easily shift the equilibrium.

densest - 2-7-2010 at 21:05

pK1 of citric acid is about 3.1, so less than 1/1000 of the Cl- could be distilled out as HCl. Not a good route, but in desperation it would produce a very little HCl.