[Histonet] normal solutions question

[Smith, Allen]

Normality is the concentration of the reactive species.  If the reactive
species is hydrogen ions, you have to look up (or memorize) the number of
hydrogen ions per molecule of acid.
If someone gives the formula of lactic acid as CH3CHOHCOOH, you are supposed
to know that only the last hydrogen dissociates in water and reacts with
hydroxide ions.  Thus, 1 molar lactic acid is 1 normal.  If the formula of
lactic acid is given as C3H6O3, you have to look up the structural formula.
Sulfuric acid is H2SO4.  There are two dissociable hydrogens.  Thus, 1 molar
sulfuric acid is 2 normal (or, better, 2 normal in hydrogen ions).  
Phosphoric acid is H3PO4.  There are three dissociable hydrogens.  Thus 1
molar phosphoric acid is 3 normal in hydrogen ions.
Citric acid also has 3 dissociable hydrogens, and 1 molar citric acid is 3
normal in hydrogen ions.  The molecular weight is 192 daltons per molecule
(or 192 grams per mole).  192 grams of citric acid in a liter of solution
would be a 1 molar or 3 normal solution.  If you want a 1 normal solution,
you will need only 1/3 as much citric acid per liter.  Thus, 64 grams of
citric acid in a liter of solution would be 0.333 molar or 1 normal, and 64
would be the "normal weight" of citric acid (assuming that you are concerned
with the normality of dissociable hydrogen, which is usually the case).

Allen A. Smith, Ph.D.
Professor of Anatomy
School of Graduate Medical Sciences 
Barry University 
Miami Shores, FL

-----Original Message-----
From: histonet-bounces <@t> lists.utsouthwestern.edu
[mailto:histonet-bounces <@t> lists.utsouthwestern.edu] On Behalf Of
JCarpenter764 <@t> aol.com
Sent: Wednesday, January 14, 2004 2:54 PM
To: histonet <@t> lists.utsouthwestern.edu
Subject: [Histonet] normal solutions question


Thank You guys for all the responses i have received...but im still STUCK  i

don't understand how to come up with the positive valence, or number of 
dissociable or replaceable hydrogen ions.....this is the number that i
divide the 
molar weight with to get the normal weight....every problem i have worked
out i 
seem to be dividing by 2 and that doesn't make since to me.
_______________________________________________
Histonet mailing list
Histonet <@t> lists.utsouthwestern.edu
http://lists.utsouthwestern.edu/mailman/listinfo/histonet
           
                       
                
The information transmitted is intended only for the person or entity to which it is addressed and may contain confidential, and/or privileged material. No confidentiality or privilege is waived or lost by any errant transmission. If you receive this message in error, please immediately delete it and all copies of it from your system and notify the sender.  E-mail transmission cannot be guaranteed to be secure or error-free as information could be intercepted, corrupted, lost, destroyed, arrive late or incomplete, or contain viruses.
Barry University - Miami Shores, FL (http://www.barry.edu)