(A)excess water to liquid (see structure)✓ Correct
(B)sodium stearate to pure toluene
(C)liquid diethyl ether to aqueous NaCl solution
(D)excess water to liquid (see structure)
Answer: (A)
Solution
A micelle forms only from an amphiphile, a molecule with a long non-polar tail and a polar or ionic head, and only in a medium that solvates the heads while the tails cluster away from it. The surfactant with a long hydrocarbon chain ending in an ionic head, added to excess water, aggregates with its tails pointing inward and its charged heads facing the water, giving an ionic micelle. Sodium stearate in toluene has no polar medium to drive aggregation, and diethyl ether in brine lacks the amphiphilic structure, so neither of those forms a micelle.
JEE Main · 2020 · 03 Sep 2020 · Shift 2 · Single correct option