This is a normal set of Dreiding stereomodels, molecular modelling kits devised by the Swis chemist Andre Dreiding (1919- ) in 1958 for constructing models of organic molecules. The models are based on the ball and spoke concept, with tubes representing bonds connected to points representing atomic nuclei. Dreiding models are particularly useful for demonstrating stereochemistry, the way in which atoms are arranged spatially within a molecule. The normal set pictured contains 182 separate parts. Other sets are available to construct models of specific groups of organic compounds.
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