Hi guys, I have run in this problem.
Calculate the ph of the solution obtained by mixing 50g of potassium nitrate with 1l of H2O.
Ka = 7,1 * 10^-4
I don't understand if it is a buffer solution or if ir isn't solvable.
Thank you for the replies.
Exercise on pH
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- ChenBeier
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Re: Exercise on pH
Where did you get the ka value from? The value is wrong. Potassium nitrate is a salt made by nitric acid and potassium hydroxide. Both are strong chemicals, acid and base. Also pH should be near neutral.
Ka of HNO3 = 20,89, pKa =-1,32
Normaly pH = 14 - 1/2 * (pkB - lg [c anion])
If the value is right then you would get pH 8,42
Ka of HNO3 = 20,89, pKa =-1,32
Normaly pH = 14 - 1/2 * (pkB - lg [c anion])
If the value is right then you would get pH 8,42
Re: Exercise on pH
Potassium nitrate HNO3 is a salt derived from a strong acid HNO3 and a strong base KOH. When such a salt dissolves in water, it does not affect the pH of the solution significantly because neither the cation nor the anion hydrolyzes to form H+ or OH- ions. Therefore, the solution remains neutral, and the pH should be around 7
- ChenBeier
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Re: Exercise on pH
That is what I said above. Why repetation.