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Wednesday, 12 August 2020

Optical isomerism?

Lashawnda Anteby: th% of that

Caleb Chapman: An isomer is a form of a compound that is the same in the number and type of atoms but different in structure or how they are hooked together. Optical isomers actually look the same but are affected differenrly by light. They turn light right or left. They are called cis or trans isomers. Sometimes in the body they just dont work if they are not the right or left turning molecule.

Leif Andreason: Optical isomerism is a form of stereo-isomerism (the "handed-ness" of an atom, i.e., your left and right hands are identical in terms of parts, but are mirror images of each other (or can't be superimposed exactly)).Optical isomers accordingly named because of their *measured experimental* effect on polarised light. Simple substances which show optical isomerism exist as two isomers known as enantiomers.A solution of one enantiomer rotates the plane of polarisation in a clockwise direction. This enantiomer is known as the ! (+) form.A solution of the other enantiomer rotates the plane of polarisation in an anti-clockwise direction. This enantiomer is known as the (-) form. If the solutions are equally concentrated the amount of rotation caused by the two isomers is exactly the same - but in opposite directions.If a 50:50 solution of each enantiomer is examined, there is no rotation (the effect from each form cancels each other out).In order to see optical isomerism, a molecule needs to have a stereo-center. BUT, not all molecules with stereocenters will demonstrate optical isomerism....Show more

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