Textbook of Soil Physical Chemistry by P. K. Das provides a systematic and simplified treatment of the physical and chemical processes that govern soil properties, nutrient availability, and soil management. Designed in accordance with the ICAR postgraduate course outline for Soil Science, the book covers fundamental chemical principles applied to soil systems, chemical composition of soils, clay mineralogy, mineral stability, soil charges, colloids, cation exchange, anion and molecular adsorption, phosphate fixation, potassium chemistry, soil reaction, salt-affected soils, electrochemical properties, mineral equilibria, nutrient adsorption and desorption, waterlogged soils, and soil organic matter. The book emphasizes the relationship between soil chemistry, mineralogy, soil fertility, and nutrient availability, making complex concepts accessible to postgraduate students and useful for teaching and academic reference