Question

Which of the following show(s) optical activity at 100 mM concentration in water?

• A. Solution of NaCl
• B. Solution of D-Glucose
• C. Solution of Glycine
• D. Solution of L-Proline

Hint:

Chiral molecules exhibit optical activity due to their ability to rotate plane-polarized light.

Answer 1

The Correct Option is B, D

To determine which solutions exhibit optical activity, we need to consider if the substances are optically active.

Step 1: Solution of NaCl
NaCl (sodium chloride) is an ionic compound and does not exhibit optical activity, as it does not have chiral centers or asymmetric carbon atoms.
Thus, \( \boxed{A} \) is incorrect.

Step 2: Solution of D-Glucose
D-Glucose is a chiral molecule and exhibits optical activity because of its asymmetry. It can rotate plane-polarized light, thus showing optical activity.
Thus, \( \boxed{B} \) is correct.

Step 3: Solution of Glycine
Glycine is the only amino acid that is not chiral because its side chain is a hydrogen atom, making it achiral. Therefore, it does not exhibit optical activity in solution.
Thus, \( \boxed{C} \) is incorrect.

Step 4: Solution of L-Proline
L-Proline is a chiral molecule and shows optical activity, as it has a chiral center and can rotate plane-polarized light.
Thus, \( \boxed{D} \) is correct.

Final Answer:
The correct answers are \( \boxed{B} \) and \( \boxed{D} \).