autacoid, 130 auto-ionization in mass spectrometry , 130 autocatalytic reaction, 130 automation in analysis , 130 automerization, 130 autophobicity, 131 autoprotolysis, 131 autoprotolysis constant, 131 autoradiograph, 132 autoradiolysis, 132 auxiliary electrode, 132 auxochrome [obsolete] , 132 auxotrophy, 132 average current density, 133 average degree of polymerization, 133 average life in nuclear chemistry, 133 average rate of flow in polarography , 133