Cc1cccc2c(N=Nc3ccc(S(=O)(=O)Nc4cccc(Cl)c4)cc3[N+](=O)[O-])c(O)[nH]c12
The negative base-10 logarithmic of dissociation constant (pka) for an acid is a direct consequence of the underlying thermodynamics of the dissociation reaction; the pKa value is directly proportional to the standard Gibbs free energy change for the reaction. What is the pka value of this molecule?