Above the critical micelle concentration (CMC), the option which correctly describes the variation of molar conductivity with increase in concentration of sodium dodecylsulphate in aqueous solution is
(a)molar conductivity increases sharply, but the solution does not remain colloidal
(b)molar conductivity decreases sharply, but the solution remains colloidal
(c)molar conductivity decreases sharply and dissociation into monomers also occurs sharply
(d)molar conductivity increases sharply with large loss of entropy
Answer
Answer: B ✓ checked by 4AB · confidence high
Explanation
Above the CMC the surfactant ions aggregate into micelles that bind counter-ions, so the molar conductivity drops sharply while the solution stays colloidal.