This book has been written as per the syllabus prescribed by Sethu Institute of Technology (SIT), Virudhunagar for the First Semester of Engineering Chemistry students. The book has been developed in view of the recent development of the subject. The book covers important topics such as Ionic and Electrovalent Bond, Covalent Bond, Variable Valency, Coordinate or Dative Bond, Complex Ions, Effect of Water on Rocks and Minerals, Types and Effects of Impurities in Water, Methods of Treatment of Water for Domestic & Industrial Purpose, Nernst Theory, Standard Electrode Potentials, Galvanic Series, Reversible Cells, Polarization, How to Prevent Corrosion, Mineral Material, Properties of Soil Material, Sorption Process in the Soil, Cation Exchange in Soil, Visible Spectroscopy, Ultraviolet Spectroscopy, X-ray, Diffractometer, Atomic Absorption Spectrometry, Chromatography etc. have been explained in lucid manner. The book is sincerely offered to students and teaching fraternities associated with engineering chemistry from various engineering and technological institutions all over the country.