Question

Jika diketahui harga pH larutan NH3 0,1 M sebesar
11, maka harga pH larutan NH4CI 0,01 M adalah....
A .3
D. 8,5
E. 9
C. 5,5
B. 5
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Answer 1

PH = 11
pOH = 14 - 11 = 3

pOH = - log [OH-]
3 = - log [OH-]
[OH-] = 10^(-3)

[OH-] = akar (Mb × Kb)
10^(-3) = akar (0,1 × Kb)
10^(-6) = 10^(-1) × Kb
Kb = 10^(-5)

[H+] = akar (Kw/Kb × [garam])
[H+] = akar (10^(-14) / 10^(-5) × 0,01)
[H+] = akar (10^(-11))
[H+] = 10^(-5,5)

pH = - log [H+]
pH = - log (10^(-5,5))
pH = 5,5