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Re: equivalents
>Greg,
>
>You must be having a bad day today! :-)
>
>Not only you defined Mole instead of equivalent, but in your second
>communication also assigned a charge of 1 to magnesium, which has a
>charge of 2! (After all, magnesium is an alkaline earth metal.)
Yes, indeed! I don't know where my head was when I wrote that +1
magnesium charge <shaking head> Guess I need to slow down... it's
just really been hectic for me lately.
And at the risk of probably making another stupid mistake ;-) let me
just address the mole vs equivalent thing with a message I sent to
Paul Sears ealier (we've been having a little private discussion on
the matter ;-))
"I didn't want to bring in moles because I didn't want to confuse
people since in the discussion moles and equivalents are, well,
equivalent. 1 mole of calcium ions is the same thing as 1 equivalent
of calcium ions. But, 1 mole of calcium ions has 2 equivalents of
positive charge. I think what you're saying though is that by using
the term "equivalent" we imply that we are counting charge. That may
be the convention in aquarium water terminology, but in my experience
that is not the convention when speaking chemically... at least not
among organic chemists ;-)"
And just let me add I know we're not organic chemists here, I just
meant that when I gave the definition it was in the strictest
chemical meaning (i.e. the general concept of equivalence).
Equivalent is the same as mole until you define in what terms the
equivalence is (in this case charge... as you soon as you define in
terms of charge, they are no longer the same).
-Greg Morin
--
Gregory Morin, Ph.D. ~~~~~~~Research Director~~~~~~~~~~~~~~
Seachem Laboratories, Inc. www.seachem.com 888-SEACHEM
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~