Question

Every conductivity cell has a definite value for its cell constant.

1. What is cell constant? 

2. How is it related with specific conductance? 

3. Calculate the cell constant of a conductivity cell containing 0.05M KCl solution, whose resistance is 100 ohm and conductivity is 0.0075 ohm^-1 cm^-1

Answer 1

1. The quantity ℓ/A is called cell constant.

A = Area of cross section of the electrodes.

ℓ = distance of separation of two electrodes.

2. Specific conductance = Cell constant × Conductance

3. Cell constant = Specific conductance × Resistance

= 0.0075 ohm 1 cm^-1 × 100 ohm = 0.75 cm^-1