A specific rigid conductivity cell containing a aqueous solution registers an electrical resistance — Electrochemistry Chemistry Question
Question
A specific rigid conductivity cell containing a $0.1\text{ M}$ aqueous $KCl$ solution registers an electrical resistance of $R_1$. The exact same cell is carefully washed and refilled with a completely different $0.01\text{ M}$ aqueous $NaCl$ solution, registering a new resistance of $R_2$. Which of the following parameters strictly and absolutely remain constant between the two distinct measurements?
💡 Solution & Explanation
A conductivity cell is a fixed physical apparatus. The distance between the electrodes ($l$) and their cross-sectional area ($A$) are rigid physical constants. Therefore, the ratio ($l/A$), known as the cell constant ($G^*$), strictly remains constant regardless of the electrolyte used. Specific conductance ($\kappa$) and molar conductivity ($\Lambda_m$) change based strictly on the nature and concentration of the dissolved ions.