Sebanyak 2,05 gr CH3COONa (Mr = 82) dilarutkan dalam air samlai volume 100 mL, pH larutan yaitu... (Ka CH3COOH = 10^-5)

m CH3COONa : 2,05 gr
Mr CH3COONa : 82
Volum larutan : 100 mL=0.1 L
ka CH3COOH : 10^-5

mol CH3COONa
=m/Mr
=2,05/82
=0,025
Molaritas CH3COONa
= n/V
= 0,025/0,1
= 0,25

(OH-)
=√kw/ka x M
=√10^-14/10^-5 x 25.10^-2
=√10^-11.25
=10^-5,5 x 25

POH
=-log10^-5,5 x 25
=5,5-log25

PH
=14-(5,5-log25)
=8,5+log25
=