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Each specification has been broken down into statements and mapped to individual teaching activities.
Optical isomerism occurs when a molecule is not superimposable with its mirror image. It is so called because the two isomers are each optically active , that is, they rotate the plane of polarized light in opposite directions. The symbol Λ ( lambda ) is used as a prefix to describe the left-handed propeller twist formed by three bidentate ligands, as shown. Likewise, the symbol Δ ( delta ) is used as a prefix for the right-handed propeller twist. 
These are not written for the international A-levels but there will be overlap with them.
In chemistry , a coordination complex consists of a central atom or ion, which is usually metallic and is called the coordination centre, and a surrounding ...