Question

A conductivity cell filled with 0.02 M AgNO₃ gives at 25°C resistance of 947 ohms. If the cell constant is 2.3 cm^-1, what is the molar conductivity of 0.02 M AgNO₃ at 25°C?

Answer 1

Given: Concentration = C = 0.02 M AgNO₃

Resistance of solution = R_soln = 947 Ω

Cell constant = b = 2.3 cm^-1

Molar conductivity = Λ_m = ?

Conductivity of soln = k

`= "Cell constant"/(R_("soln")) = b/(R_("soln")) = 2.3/947`

= 0.002429 Ω^-1 cm^-1

Molar conductivity, Λ_m

`= (k xx 1000)/C = (0.002429 xx 1000)/0.02 = 121.5  Ω^-1  "cm"^2  "mol"^-1`