The ICE approach for the equilibrium yields;
CHCO2H+H2O⇋H3O++CH3CO2−
The initial concentration of CH3CO2H =0.20
Change =x
Equilibrium concentration=0.20−x
The initial concentration of CH3CO2−
.=0.20
Change=x
Equilibrium concentration=0.20+x
Substituting the equilibrium concentration terms into the Ka expression, assuming x⋘ 0.20 and solving the simplified equation for x yields
x=1.8×10−5
[H3O+]=0+x=1.8×10−5 pH=−log[H3O+]=−log(1.8×10−5M)=4.74
Comments
Leave a comment