From: SFPhysics@aol.com
Date: Mon, 19 Oct 1998 19:41:50 EDT
To: pinhole@exploratorium.edu
Subject: NaCl as Electrolyte, etc. vs. H2SO4
Going back to my notes on sulfuric acid for dissociation of water into H2 and
O2, I find that for 200 ml of water you only need a few ml of sulfuric acid.
A molar solution of about .05 will work just fine. The use of any other
electrolyte such as ammonium sulfate is not justified unless handling the
liquid acid (20 molar) is not acceptable.
Sodium Chloride was suggested but this will not work as sodium is deposited on
one electrode where it immediately reacts to make sodium hydroxide. The other
electrode starts to give off chlorine gas which if collected properly is quite
a nice yellow-green for students to see. Sodium chloride as an ionic compound
is more easily dissociated than the water molecules.
Now I could be all wet on the above so corrections are welcome. All of this
is from my stone-age years.
Al Sefl
SFPhysics@aol.com