Chemistry - STEREO ISOMERISM Question with Solution | TestHub

The compound is 1,3-dimethylcyclobutane-2,4-dicarboxylic acid: CH₃ groups at C₁ and C₃, CO₂H groups at C₂ and C₄. Its six up/down patterns are: (CH₃ up,up / CO₂H up,up), (up,up / up,down) and (up,up / down,up) - each with a plane of symmetry through the C₂-C₄ diagonal; (up,down / up,down) - plane of symmetry through the C₁-C₃ diagonal; and (up,up / down,down) and (up,down / down,up) - each with a centre of symmetry. Every stereoisomer has a plane or centre of symmetry, so none is optically active.

Ans. (C) Zero.