skip - 18-6-2016 at 08:53
I have some old muriatic acid, its been opened . Couple yrs old Id estimate . This sounds dumb to me but, Im wondering is it still good to use in
reactions ?
DraconicAcid - 18-6-2016 at 09:01
Probably. At worst, some of the acid will have evaporated, and it won't be as high a concentration as it once was.
skip - 18-6-2016 at 09:04
thank you.
CRUSTY - 18-6-2016 at 14:48
You could try titrating a small bit of it with NaOH or another base to determine the pH. Unless there has been anything stuck into it, it's cloudy, or
a color other than clear, it's likely fine.
AJKOER - 23-6-2016 at 13:34
To a known volume of the HCl, add a mixture of NaCl and NaHCO3 in excess. Collect the CO2 gas over a liquid in which CO2 does not dissolve (cooking
oil,....).
Every 22.4 liters of CO2 collected equals 1 mole and correspondingly, a mole of HCl:
HCl + NaHCO3 = NaCl + H2O + CO2 (g)
The role of the added NaCl is to limit the amount of CO2 that could possible be dissolved, which would lead to an under estimation.
Alternately, react the HCl with an excess of Zn and collect the H2 over water:
2 HCl + Zn = ZnCl2 + H2 (g)
Now, each mole of H2 collected corresponds to two moles of HCl. A possible issue is that heated water does react with the zinc metal liberating some
hydrogen as well, so this path may slightly over estimate.
[Edited on 23-6-2016 by AJKOER]