Question

If resistivity of 0.8 M KCI solution is 2.5 × 10^-3 Ω cm. Calculate molar conductivity of solution?

Options

• 2 × 10⁵ Ω^-1 cm² mol^-1

• 5 × 10⁵ Ω^-1 cm² mol^-1

• 4 × 10⁵ Ω^-1 cm² mol^-1

• 3 × 10⁵ Ω^-1 cm² mol^-1

Answer 1

5 × 10⁵ Ω^-1 cm² mol^-1

Explanation:

Given,

Resistivity (p) = 2.5 × 10^-3 Ω cm

M = 0.8 m

We know that,

k = `1/rho = 1/(2.5 xx 10^-3)`

= 4 × 10² Ω cm^-1

Also,

molar conductivity (λ_m) = `"k" xx 1000/"M"`

`= (4 xx 10^2 xx 1000)/0.8`

`lambda_"m" = 5 xx 10^5  Omega  "cm"^2  "mol"^-1`