The Adsorption of Thiomalic Acid on the Mercury Electrode

R. Thiagarajan; K. B. Sarangapani; V. Balaramachandran; S. Venkatakrishna Iyer

The Adsorption of Thiomalic Acid on the Mercury Electrode

R. Thiagarajan ¹, K. B. Sarangapani ², V. Balaramachandran ², S. Venkatakrishna Iyer ²

Affiliations
1 Department of Physics, Urmu Dhanalakshmi College, Trichy, India
2 Central Electrochemical Research Institute, Karaikudi 623006, India

The adsorption of thiomalic acid on the mercury electrode from 0.2 NH₃PO₄ solutions was studied using capillary electrometer. Thermodynamic parameters like the charge on the metal surface and the surface excess of organic molecules adsobred have been obtained for different concentrations of the adsorbate. A thorough analysis of the adsorption data reveals the fact that the adsorption of thiomalic acid on mercury obeys Temkin's adsorption isotherm. The variation of free energy of adsorption with charge has been suitably explained.