In the development of chemistry, according to the different types of molecules studied, the research methods, purposes and tasks are different, and many branches of different levels are derived. Before the 1920s, chemistry was traditionally divided into four branches: inorganic chemistry, organic chemistry, physical chemistry and analytical chemistry. Since the 1920s, due to the rapid development of the world economy, the birth of electronic theory and quantum mechanics of chemical bonds, and the rise of electronic technology and computer technology, chemical research has gained new means in theory and experimental technology, which has led to the rapid development and brand-new appearance of this discipline since the 1930s. The content of chemistry is generally divided into seven categories, including biochemistry, organic chemistry, polymer chemistry, applied chemistry and chemical engineering, physical chemistry and inorganic chemistry, with seven branches.

According to the development of chemistry today and its mutual penetration with astronomy, physics, mathematics, biology, medicine, earth science and other disciplines, chemistry can be classified as follows:

1, inorganic chemistry

Elemental chemistry, inorganic synthetic chemistry, inorganic polymer chemistry, inorganic solid chemistry, coordination chemistry (that is, complex chemistry), isotope chemistry, bioinorganic chemistry, organometallic chemistry, metalloenzyme chemistry, etc.

organic chemistry

2. General organic chemistry, organic synthetic chemistry, metal and nonmetal organic chemistry, physical organic chemistry, bioorganic chemistry and organic analytical chemistry.

3. Physical chemistry

Structural chemistry, thermochemistry, chemical thermodynamics, chemical kinetics, electrochemistry, solution theory, interface chemistry, colloid chemistry, quantum chemistry, catalysis and its theory.

4. Analytical chemistry

Chemical analysis, instrument and new technology analysis. Including performance measurement, monitoring, various spectral and photochemical analysis, various electrochemical analysis methods, mass spectrometry, various electron microscopes, imaging and morphology analysis methods, online analysis, activity analysis, real-time analysis and so on. Various detection methods of physical and chemical properties and physiological activities, separation methods such as extraction, ion exchange, chromatography and mass spectrometry, combined separation analysis, combined synthesis and separation analysis, etc.

5, polymer chemistry

Natural polymer chemistry, polymer synthetic chemistry, polymer physical chemistry, polymer application, polymer physics.

6. Nuclear chemistry

Radioelement chemistry, radioactive analytical chemistry, radiochemistry, isotope chemistry, nuclear chemistry.

biochemistry

7. General biochemistry, enzyme, microbial chemistry, phytochemistry, immunochemistry, fermentation and bioengineering, food chemistry, coal chemistry, etc.

Other frontier disciplines related to chemistry include geochemistry, marine chemistry, atmospheric chemistry, environmental chemistry, cosmic chemistry, interstellar chemistry and so on.