100 mL HCN 0,2 M + 10 mL KOH 0,2 M Ka=1.10pangkat 4

N HCN = 100 * 0.2 = 20
n KOH = 100 * 0.2 = 20

HCN + KOH –> KCN + H2O

n KCN = 1/1 * 20 = 20

[KCN] = 20/200 = 0.1

[OH-] = akar Kw/Ka . [g]
= akar 10^-14/10^-5 * 10^-1
= akar 10^-10
= 10^-5

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