1) In specific acid catalysis, the undissociated acids do not contribute.

2) The solubility of dissociated proteins would decrease more slowly than the undissociated proteins when the speed of ultracentrifugation getting higher.

3) All the sebacic acids were exist as the dianion, and there was no undissociated molecules.

4) Lactic acid and acetic acid showed an inhibitory effect toward bacillus subtilis if the undissociated form was more than 0.683% and 0.256%, respectively.

5) Water species adsorb On the surface mainly in the form of undissociated molecules.