Question

Define internal compensation

Answer 1

In case of meso compounds, which has two chiral centers, the configuration of the compound is either R,S or S,R. Looking into the optical activity, meso compounds(contain plane of symmetry) are optically inactive as rotation of one chiral center is compensated by rotation of second chiral center and since, the rotation occurs within the molecule, it is known as internal compensation

Answer 2

the compensation occur within molecules, so it's called internal compensation, again in case of recemic features , 50% mixture of enanteomers the net rotation is zero because rotation of one isomar is compensated by it's enanteomers so it's called internal compensation
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