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KUNCI
JAWABAN
A. Objektif
VI
B. Essay
1. HCOONa(aq) = Na+(aq) + HCOO (aq)
n HCOO = (koef HCOO )/(koef HCOONa) x n HCOONa
n HCOO = 1/1 x 8 mmol
[H+] = Ka x (mol asam lemah)/(mol basa konjugasinya)
[H+] = 10-4 x 2/8= 2,5 x 10-5
pH = - log [H+]
pH = - log (2,5 x 10-5)
pH = 5 - log 2,5
