Question

An electric current is passed through an aqueous solution (buffered at pH = 6.0) of alanine (pl - 6.0) and ariginine (pl = 10.2). The two amino acids can be separated because ?

• A. Alanine migrates to anode, and arginine to cathode.
• B. Alanine migrates to cathode, and arginine to anode.
• C. Alanine does not migrate, while arginine to anode.
• D. Alanine does not migrate, while arginine migrates to anode.

Answer 1

The correct option is C

Alanine does not migrate, while arginine to anode.

At the given pH (6) of the solution, alanine (pl = 6.0), exists as a dipolar ion while arginine (pl = 10.2) exists as a cation. Hence on passing an electric current, alanine will not migrate to any electrode, while arginine will migrate to cathode.