Question about Molarity and Normality

[bonoz]

If a solution is 0.1 N, then does it mean that it is 0.1 M as well? or could it also be a 0.05 M solution if it is diprotic? or 0.033 M if it is triprotic?

I know that a 1 M solution of something like HCl would be 1 N, and 1 M of H2SO4 would be 2 N; 2 M of the aforementioned solutions would be 2 N and 6 N, respectively?

Basically, I am unsure how 0.1 N solution converts into Molarity?

Cheers

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[sleepy425]

i think you mean 2 N and 4 N respectively, not 2 and 6.

N=M*(#of acidic protons)

So (# of acidic protons) for HCl is 1, for H2SO4 is 2, for H3PO4 is 3. It's pretty straightforward

 

[crazypharma]

i think you mean 2 N and 4 N respectively, not 2 and 6.

N=M*(#of acidic protons)

So (# of acidic protons) for HCl is 1, for H2SO4 is 2, for H3PO4 is 3. It's pretty straightforward

agreed.. it depends on for what solution you are finding /converting molarity and normality

 

[Artful Dodger]

i think you mean 2 N and 4 N respectively, not 2 and 6.

N=M*(#of acidic protons)

So (# of acidic protons) for HCl is 1, for H2SO4 is 2, for H3PO4 is 3. It's pretty straightforward

Yep, exactly. Good post. And for the original poster, molarity doesn't take into account # of acidic protons. In addition, there's other ways to measure concentration such as Analytical, formal, osmolarity, etc. Look into it if you have time or take an Analytical Chemistry course.

 

[LaCasta]

So a 1N solution of a diprotic acid would actually be 1/2M correct?

 

[sleepy425]

So a 1N solution of a diprotic acid would actually be 1/2M correct?

yep. The idea is that, even though you have .5 M of the acid, it would take 1 M of a monobasic base (something like NaOH or KOH or something that can only accept one proton per molecule) to reach the equivalence point of a titration. So instead of writing the acid as .5 M, we can write it as 1 N, and then we have 1 N of acid and 1 N base, which is 1:1, even though it is actually .5 M acid to 1 M base.

 

[bonoz]

yep. The idea is that, even though you have .5 M of the acid, it would take 1 M of a monobasic base (something like NaOH or KOH or something that can only accept one proton per molecule) to reach the equivalence point of a titration. So instead of writing the acid as .5 M, we can write it as 1 N, and then we have 1 N of acid and 1 N base, which is 1:1, even though it is actually .5 M acid to 1 M base.

So formula for Normality can be though of as:

N = M*(acid or base equivalents)

?

 

[chemtopper]

Normality = Molarity X acidity or basicity of a base and acid respectively
Molarity = normality /acidity or basicity
NaOH has one
Ca(OH)2 has two
It depends on the number of ionizable ions (OH-) and (H+)
Concept is simple and straight with acids and bases .
But in redox reactions you have to see how many electrons are gained or lost during the reaction