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Why are chiral molecules optically active?

Answer 1

Optically active molecules are not limited to chiral ones.

Optically active means they rotate the plane of polarization. Either to the right (#D#) or to the left (#L#).

If we have a molecule with a chiral (asymmetrical) #C#-atom in it, it is possible to have two versions of the molecule, one being the mirror image of the other.(try this with the balls-and-sticks). Just like a pair of gloves.

One stereo-isomer will rotate the plane of polarization in one direction, while the other will mirror this and rotate it in the opposite direction.

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Answer 2

Ellie Adams

Chiral molecules are optically active because they lack a plane of symmetry, causing them to rotate the plane of polarized light. This rotation occurs due to the interaction between the chiral molecule and the electric field vector of polarized light, resulting in a net rotation of the plane of polarization. The extent of rotation depends on factors such as the concentration of the chiral molecules, the path length of the light through the solution, and the specific properties of the molecules involved.

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Answer from HIX Tutor

When evaluating a one-sided limit, you need to be careful when a quantity is approaching zero since its sign is different depending on which way it is approaching zero from. Let us look at some examples.