Chemical Forums
Chemistry Forums for Students => Physical Chemistry Forum => Topic started by: Luisa2901 on December 09, 2023, 12:49:57 PM
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Do you have any suggestions about this question?
Calculate the mass of solid sodium acetate that must be added to 200 mL of a solution containing 0.200 mol/L silver nitrate and 0.100 mol/L nitric acid so that silver acetate (Ksp = 2.30x10-3) begins to precipitate.
I know that AgNO3 is a soluble salt and HNO3 is a strong acid, so the initial concentrations of Ag+ and H+ will be 0.2 mol/L and 0.1 mol/L. I am having trouble figuring out how the H+ of the acid will affect the equilibrium.
Nac2h3O2---> Na+ + C2H3O2-
C2H302- +Ag+ ---> AgC2H302
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Acetic acid is a weak one, isn't it?
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So I have to consider that C2H302- will react with the H+ of HNo3 to form acetic acid?
Nac2h3O2---> Na+ + C2H3O2-
x x x
C2H302- + H+---> HC2H3O2 K=1/ka (acetic acid)
x 0.1 0
-y -y y
x-y 0.1-y y
C2H302- +Ag+ ---> AgC2H302
x-y -z 0.2- z
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So I have to consider that C2H302- will react with the H+ of HNo3 to form acetic acid?
Yes.
Not sure what you are trying to do with z, you are looking for the moment where nothing precipitated yet.