Objective and Learning Outcome

Principles governing ion exchange, retention, chemical equilibria for precipitation and synthesis and chemical remediation processes in soil are discussed. The students should be able to predict release of ions and fate of chemicals in soil by using models.

Course Contents

1. Chemical equilibria in soil, water and solute interactions

2. Soil solution-solid interaction

3. Mineral dissolution: congruent and incongruent

4. Neo-formation of minerals in soil

5. Thermodynamics and applications in soil

6. Organic matter: composition and fractionation

7. Surface chemistry of soil matrix

8. Sorption and desorption models

9. Ion exchange: selectivity coefficients, equivalent fraction concept

9.1 Hysteresis in ion exchange

9.2 Anion exclusion

9.3 Complementation effect

9.4 Zeta potential

10. Reactions of metal chelates in soils

11. Chemical behavior of ions / elements in aerated and submerged soils

12. Buffering reactions in soil

13. Chemical remediation of contaminated soils and water


1. Determination of CEC and base saturation

2. Developing K vs Ca + Mg activity ratios in laboratory

3. Determination of phosphorous adsorption isotherm

4. Comparative fit (data from 3) to Freundlich and Langmuir models

5. Developing titration curves

Books Recommended

1. Bohn, H.L., B.L. McNeal and G.A.O. Connor. 2001. Soil Chemistry. 3rd Ed. John Wiley & Sons Inc., NY, USA.

2. Essington, M. E. 2004. Soil and Water Chemistry. CRC Press, Boca Raton, FL, USA. 3. McBride, M. 1994. Environmental Chemistry of soils. 406 pp. Oxford University Press. 4. Sparks, D.L. 2003.

3. Environmental Soil Chemistry. 2nd Ed. Academic Press, San Diego, CA, USA. 5. Sposito, G. 2008.

4. The Chemistry of Soils. 2nd Ed. Oxford University Press, NY, USA. 6. Sriniwas, P. 2010.

5. Soil Chemistry. Oxford Book Company, New Delhi, India. 7. Tan, K.H. 2009. Environmental Soil Science. 3rd Ed. CRC Press, Greenwatch Georgia, USA.

Assessment Criteria

Sessional: 08 (project, presentation, participation)

Project: 04

Presentation: 02

Participation: 02

Mid exam: 12

Final exam: 20

Practical exam: 20

Course Material