Q20 of 30 Page 1

The electrical resistance of a column of 0.05 M NaOH solution of diameter 1 cm and length 50 cm is 5.55 x103ohm. Calculate its resistivity, conductivity and
molar conductivity.

Area of the column with radius (r) 0.5cm (radius =) is:


A = π×r2 = 3.14(0.5)(0.5) = 0.785cm2.


Length (l) = 50cm and Resistance (R) = 5.55×103Ω


We know, R =


Or, ρ = = = 87.14 Ωcm


Conductivity κ = = = 0.01147 Scm-1.


Molarity (M) = 0.05 [M]


We know,


Molar conductivity = = = 229.4 S cm2 mol-1.


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