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This is packed with chemical and physical data including: basic constants, units conversion factors and mathematical tables, scientific terminology and symbols, physical constants of organic and inorganic compounds, molecular structure and spectroscopy, biochemistry, analytical chemistry, properties of atoms, particles, solids, fluids, polymers, atomic, molecular, optical, nuclear and particle physics, and sections on geophysics, astronomy, acoustics, and practical laboratory data and safety. (Updated annually)
Listed below are the letters and titles of the main classes of the Library of Congress Classification. Click on any class to view an outline of its subclasses in an interactive PDF format. This list is based on the Library of Congress Classification Outline.