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MODEL PAPER 2025 — Chemistry STD 12 Science — Question

Bihar BoardEnglish MediumSTD 12 ScienceChemistryMODEL PAPER 20251 Mark
MCQ
Assertion (A): For strong electrolytes, there is a slow increase in molar conductivity with dilution and can be represented by the equation
      $\Lambda_m^0=\Lambda_m-A c^{1 / 2}$
Reason (R): The value of the constant 'A' for NaCl, CaCl2, and MgSO4 in a given solvent and at a given temperature is different.
  • A
    Both A and R are true and R is the correct explanation of A
  • B
    Both A and R are true but R is not the correct explanation of A.
  • C
    A is true but R is false.
  • ✓
    A is false but R is true.
✓

Answer

Correct option: D.
A is false but R is true.
(d) A is false but R is true.
$\Lambda_m^{\circ}=\Lambda_m-A c^{1 / 2}$ is an incorrect equation, the correct equation is $\Lambda_m=\Lambda_m^0-A c^{1 / 2}$

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