Chemistry can be divided into branches according to either the substances studies or the types of study conducted. The primary division of the first type is between inorganic and organic chemistry. Divisions of the second type are physical chemistry and analytical chemistry. The original distinction between organic and inorganic chemistry arose as chemists gradually realized that compounds of biological origin were quite different in their general properties from those of mineral origin; organic chemistry was defined as the study of substances produced by living organisms. When it was discovered in the 19th century that organic molecules can be produced artificially in the laboratory, this definition had to be abandoned. Organic chemistry is most simply defined as the study of the compounds of carbon. Inorganic chemistry is the study of chemical elements and their compounds. This book has been prepared for students, researchers and teachers of chemistry.