This set contains sufficient parts to make eight atomic models. Each model is an example of the different orientations of the bonds and cover co-ordination numbers 1 to 6. The atom cores are represented by the standard Molymod® atom parts and the atomic and molecular orbital parts by colour- coded matt or pastel-coloured pieces. Lone pairs are represented by brown spheres or brown pear shaped parts. The latter is useful as protonated models of NH4+ and H3O+ may be built thus demonstrating Acid/Base theory.Contents: Hydrogen ChlorideBeryllium ChlorideWaterBoron TrihydrideAmmoniaMethanePhosphorus PentachlorideSulphur Hexafluoride