O=C1Nc2c(c(=O)[nH]c(=O)n2-c2ccc(F)cc2)C1(NS(=O)(=O)c1ccccc1)C(F)(F)F
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?