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MODEL PAPER 2025 — Chemistry STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceChemistryMODEL PAPER 20251 Mark
Question
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 $\ce{NaCl, CaCl_2},$ and $\ce{MgSO_4}$ in a given solvent and at a given temperature is different.
✓

Answer

$A$ 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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