Practice Problem 10

Use the following standard-state free energy of formation data to calculate the acid-dissociation equilibrium constant (K_a) at  for formic acid:

Compound              G_f^o(kJ/mol) 

HCO₂(aq)                    -372.3

H⁺(aq)                          0.00

HCO₂^-(aq)                   -351.0

Answer

K = 1.8 x10^-4