Question

R-2-pentanol and S-2-pentanol are different with respect to their:A. number of degrees of rotation of plane-polarized light.B. direction of rotation of plane-polarized light.

Answer 1

Answer:

B. direction of rotation of plane-polarized light.

Explanation:

Both R-2-pentanol and S-2-pentanol are isomer and optical active compound . Both are enantiomers and therefore mirror image to each other . They are different only in respect of their optical activity . One of them will rotate the plane of polarisation of polarised light to the right and the other will rotate the plane to the left . The extent of their rotation will be same . When we take a

racemic mixture of the two in the ratio of 1 :  1 , then the mixture will be optically inactive .

So the answer will be B .