COc1ccccc1-c1cc(C(F)(F)F)nc(S(=O)(=O)CCCC(=O)Nc2cc(Br)ccc2O)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?