Hi there,
I have a question which I am terribly stuck on!
I feel as though I have tried almost everything and cannot get any of the options given . I would appreciate any help that I can get!
I have attached the question below.
I used the Hendersonhasselbach equation pH=pka + log [A]/[HA]
We know that ka = 6.31 x10 ^6. I also made the assumption that 0.2mols is 0.2molL1 (not sure if I can do that though)
Final pH = 5.2, so final [H3O+] = 6.31 x10^6 so pka = final pH.
I managed to figure out the initial pH concentration which is Squareroot (Ka x [HA] = 1.12 x 10^3 molL1 then log1.12 x 103 = 2.94947
Then I tried finding the difference in pH between final and initial = 5.20 2.94947 = 2.2505 and assumed that the difference was the amount of NaOH added, but I'm completely lost. Not sure if I am doing this right at all, please help!
Thanks!
I have a question which I am terribly stuck on!
I feel as though I have tried almost everything and cannot get any of the options given . I would appreciate any help that I can get!
I have attached the question below.
I used the Hendersonhasselbach equation pH=pka + log [A]/[HA]
We know that ka = 6.31 x10 ^6. I also made the assumption that 0.2mols is 0.2molL1 (not sure if I can do that though)
Final pH = 5.2, so final [H3O+] = 6.31 x10^6 so pka = final pH.
I managed to figure out the initial pH concentration which is Squareroot (Ka x [HA] = 1.12 x 10^3 molL1 then log1.12 x 103 = 2.94947
Then I tried finding the difference in pH between final and initial = 5.20 2.94947 = 2.2505 and assumed that the difference was the amount of NaOH added, but I'm completely lost. Not sure if I am doing this right at all, please help!
Thanks!
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