Secured a copy of Timbie's book, didn't find that page very helpful.
Here's a webpage that may be of use:
http://www.wpbschoolhouse.btinternet.co ... /Y11revQs/
acidreactionequationsFHanswers.htm
Metals with sulfuric or hydrochloric acid make hydrogen. Since
HCl can release chlorine gas, better to stick with sulfuric.
Reversing the reaction can be accomplished with a carbon electrode
or compartment of activated charcoal separating the metal powder
by an ionic permeable membrane. By running current thru the two cells,
the reaction is reversed and hydrogen is generated in the C. Disscontinue
current and again the acid attacks the metal, generates more H. Applying
current again makes H at C, back and forth, indefinitely, until you need to
add more water.
The neat thing is when the acid is oxidizing the metal, the arrangement
performs as an battery cell and a current is
generated. This current
can be oscillated, stepped up in voltage, rectified and stored in another
cell, to be used in the reverse phase. You may need to add a little extra
electricity to make up for losses, and elemental energy differences
between the electrodes, so what; you get hydrogen out both
ways.
According to
General Chemistry by Linus Pauling (see Chapter 15,
esp. p. 530), The book
The Oxidation States of the Elements and Their
Potentials in Aqueous Solutions by W.M. Latimer has a table of 8
pages, allowing a person to calculate equilibrium constant values for
about 85,000 reactions. Not all of them make hydrogen, but more than a
few.
