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Re: equivalents

>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