CCCCCN1C(=O)C(Cc2ccccc2)N=C(c2ccc(O)cc2)c2cc(Cl)ccc21
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?