CS(=O)(=O)O.Cc1nc2c(C)c3c([nH]c4ccc(Cl)cc43)c(C)c2c(O)c1C
An acid's negative base-10 logarithmic dissociation constant (pKa) follows directly from its underlying thermodynamics; the negative pKa is directly proportional to its standard Gibbs free energy change. What is the negative pKa value of this molecule?