Normality

[laczlacylaci]

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I have always seen normality questions with H2SO4, NaOH, HCl (all including H+ and OH-, the atom of interest.
I usually solve them by calculating the molarity (mol/L) and then multiplying it by the # of moles of H+/OH- in the compound.

How do you calculate the normality of like KCl w/o specifying the atom of interest?
Also, what about the normality of H2O, a compound that includes H+ and OH-?

 

[laczlacylaci]

So, did some more research.

If the molecules is lets say K2CO3, which dissociates into K+ and Co3 -2, we know that CO3 can become H2CO3 when reacted with water, needing 2moles of H+ or OH-, so it would be 2*molarity=normality.

So is it essentially trying to figure out how H+ and OH- fits into the compound?

 

[aldol16]

Normality must always be stated in the context of something. Just like how you can't standardize something without a standard, you can't normalize something without a normal. Usually, normality is defined with respect to the proton because that's very useful in acid-base chemistry.

As for your second question, calculating the normality of water would be harder because it's not a strong acid/base. In other words, if you put a little bit of water (solute) into another solvent, you don't get much dissociation - not very much at all. In other words, even if your water concentration was 1.0 M, very little of that would exist as H+ and HO-. Therefore, normality loses a lot of meaning.