Use the Ky values for weak acids to identify the best components for preparing buffer solutions with the given pH values. name formula ka phosphoric acid H3PO4 CH3COOH 7.5 x 10-3 1.8 x 10-5 acetic acid formic acid HCOOH 1.8 x 10-4 pH=1.9 __ pH=5.0 __ pH=__