MHT CET Medical202621 April 2026Morning ShiftChemistryElectrochemistryActual
The molar conductance of NaCl, HCl and CH ₃ COONa at infinite dilution are 126.45, 426.16 and 91.0 S cm ^2 mol ⁻¹ respectively. Calculate the molar conductance of CH ₃ COOH at infinite dilution?
Options
- A540.48 S cm ^2 mol ⁻¹
- B201.28 S cm ^2 mol ⁻¹
- C390.71 S cm ^2 mol ⁻¹
- D698.28 S cm ^2 mol ⁻¹
Correct answer
C. 390.71 S cm ^2 mol ⁻¹
Step-by-step solution
According to Kohlrausch's law of independent migration of ions: ^ _m( CH ₃ COOH ) = ^ _m( CH ₃ COONa ) + ^ _m( HCl ) - ^ _m( NaCl ) Substituting the given values: ^ _m( CH ₃ COOH ) = 91.0 + 426.16 - 126.45 ^ _m( CH ₃ COOH ) = 517.16 - 126.45 = 390.71 S cm ^2 mol ⁻¹ Answer: 390.71 S cm ^2 mol ⁻¹