Cc1ccc(Nc2c([N+](=O)[O-])nn(-c3ccc(Cl)cc3)[n+]2[O-])cc1C
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?