O=[N+]([O-])c1cc(C(F)(F)F)cc([N+](=O)[O-])c1Sc1n[nH]c(C(F)(F)F)n1
An acid's negative base-10 logarithmic dissociation constant (pka) follows directly from its underlying thermodynamics; pKa is directly proportional to its standard Gibbs free energy change. What is the pka value of this molecule?