O=C(O)CC1(CC(=O)Nc2cc(C(F)(F)F)cc(C(F)(F)F)c2)CCCCC1
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?