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Chemistry Forums for Students => High School Chemistry Forum => Topic started by: tummy on July 09, 2018, 03:32:46 PM

Title: Net Ionic Equation of Diprotic Acids
Post by: tummy on July 09, 2018, 03:32:46 PM
Whenever we write the net ionic equation for a reaction involving sulfuric acid such as say, the reaction between dilute sulfuric acid and a solution of barium acetate, why does sulfuric acid become 2H+ + 1SO42- instead of 1H+ + 1HSO4- because sulfuric acid is only a strong acid with respect to its first ionizable proton right.
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: mjc123 on July 10, 2018, 04:35:35 AM
Well, have a think. What might encourage the reaction HSO4-  :rarrow: H+ + SO42-?
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: tummy on July 10, 2018, 09:36:37 AM
Does this have to do with the fact that it is dilute sulfuric acid?
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: mjc123 on July 10, 2018, 11:42:50 AM
Not as such. What happens with sulfuric acid and barium acetate?
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: chenbeier on July 10, 2018, 12:04:24 PM
The problem here is not the neutralisation of H+. Here the Barium and the Sulfate reacts.





Title: Re: Net Ionic Equation of Diprotic Acids
Post by: Babcock_Hall on July 10, 2018, 12:21:27 PM
@OP, Writing the balanced equation might help.
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: tummy on July 10, 2018, 02:52:05 PM
The reaction is H2SO4+Ba(C2H3O2)  :rarrow: BaSO4+2HC2H3O2. Does the 2H on acetic acid somehow then imply that in the net ionic, sulfuric acid must dissociate into 2H+?
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: chenbeier on July 10, 2018, 03:02:09 PM
Barium sulfate is not good soluble.

You write it as BaSO4

What is then the basic reaction behind.?

Think all component are in ionic form in solution.
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: tummy on July 11, 2018, 10:00:32 AM
Right, barium sulfate is insoluble so it is left alone in the net ionic equation, but acetic acid is also insoluble, so shouldn't it too be left alone in the net ionic?
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: Babcock_Hall on July 11, 2018, 10:25:23 AM
tummy,

I see a couple of problems with what you wrote.  One is that acetic acid is soluble in water: white vinegar is water and acetic acid.  Another is that I don't understand why you indicated that something should be left out of an ionic equation because it is insoluble.  However, lack of solubility is an important part of this problem.
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: chenbeier on July 11, 2018, 11:53:36 AM
In the solution we have Ba2+, CH3COO-, H+, HSO4- and SO42-.

The basic reaction is Ba2+ + SO42- => BaSO4(s)

So no need to write sulfuric acid in the half dissoziation.

Title: Re: Net Ionic Equation of Diprotic Acids
Post by: Babcock_Hall on July 11, 2018, 12:01:18 PM
tummy,

Have you learned anything about Le Chatelier's principle?
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: tummy on July 11, 2018, 12:13:26 PM
Oh my bad, I did not mean that acetic acid was insoluble, I meant that it was a weak acid, so both Barium Sulfate and acetic acid should be left untouched in the net ionic because we do not write weak acids as dissociated in net ionic right? Also I have learned the basic principle of Le Chatelier's.
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: Babcock_Hall on July 12, 2018, 10:15:53 AM
Do you think that LeChatelier's principle might be applied to this question in some way?
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: tummy on July 12, 2018, 11:48:36 AM
Not really, does it have to do with adding more reactants?
Title: Re: Net Ionic Equation of Diprotic Acids
Post by: Babcock_Hall on July 12, 2018, 12:12:06 PM
As you suggested, one way to shift the equilibrium is to add more reactants.  What is another way, one that involves products?