Resistance of a conductivity cell filled with 0.1 M is 100 ohm. If the resistance of the same cell when filled with 0.02 M KCl solution is 520 ohms, calculate the conductivity and molar conductivity of the 0.02 M KCl solution. Conductivity of 0.1 M KCl solution is 1.29*10-2 S cm-1.

Cell constant can be calculated using 0.1 M KCl

= κ × R

= 0.0129 * 100

= 1.29 cm-1

Calculating conductivity of 0.02 M KCl solution

κ = Cell constant / Resistance

= 1.29 / 520

= 2.48 * 10-3 S cm-1

Therefore, molar conductivity:

Λm = 103 κ / M

= 103 * 2.48 * 10-3/0.02

= 124 S cm2 mol-1

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