The behaviour of chloranilic acid at the
dropping mercury electrode has been techniques of ordinary and of alternating
current polarography. A new type of tensammetric wave has been encountered,
which is probably an outcome either of multilayer adsorption and/or of a change
in state of the adsorbed film. At the same time, a new tensammetric phenomenon,
the exchange of one species of surface-active molecules against another, has
been observed.
Alternating current polarography can be
used for estimating chloranilic acid at concentrations as low as 10-7M,
whereas conventional polarography does not permit analysis at concentrations
below 10-5M.