It was discovered recently that the charge of gas bubbles in aqueous solution can be reduced and even reversed by the addition of multivalent inorganic salts. In this work, the effect of LaCl 3 on the charge of bubbles was investigated and found to have an effect similar to that previously observed with AlCl 3 and MgCl 2. The electrokinetic behavior of gas bubbles was affected slightly by LaCl 3 additions at low concentrations but changed markedly at high concentration (1 × 10 −3 mol dm −3) of LaCl 3. A reversal of bubble charge was observed and this is attributed to the specific adsorption of La 3+ in the lower pH region and to the formation of La(OH) 3(s) precipitate at the gas—liquid interface in the alkaline pH region.