Which term of molar conductivity is used when the concentration of electrolyte approaches to zero ?
Answer & explanation
Correct answer: option 4
The correct answer is Option (4) → Limiting molar conductivity
Molar conductivity, Λm, increases as a solution is diluted. When the concentration approaches zero, it reaches a limiting value called the limiting molar conductivity, Λm°. For strong electrolytes it is found by extrapolating the plot of Λm against √c to zero concentration:
\( \displaystyle \Lambda_m=\Lambda_m^{\circ}-A\sqrt{c} \)
NCERT (2026-27 edition):
Variation of Conductivity and Molar Conductivity with Concentration – “… Molar conductivity increases with decrease in concentration. … When concentration approaches zero, the molar conductivity is known as limiting molar conductivity and is represented by the symbol Λ°m.”