Question

Larutan penyangga terdiri dari 150 mL larutan HCN 0,1 M Ka = 4.10^-4 dan 100 mL KCN 0,1 M memiliki pH sebesar .....
a. 4+log 6
b.4-log6
c. 4
d. 6-log4
e.6+log4
bantu pakai caranya yaaa

Answer 1

Mol HCN = M x V = 0,1 × 150 = 15 mmol
mol KCN = M × V = 0,1 × 100 = 10 mmol [H+] = Ka × a/g
[H+] = 4.10^-4 × 15/10
[H+] = 4. 10^-4 × 1,5
[H+] = 6.10^-4

pH = -log [H+]
pH = -log 6.10^-4
pH = 4 - log 6
jawaban b
semoga membantu

Answer 2