Calculate molar conductivity, conductivity, or molar concentration from any two inputs with unit conversions in SI and imperial units.

Molar Conductivity Calculator

Enter any 2 values to calculate the missing variable


Related Calculators

Molar Conductivity Formula

The calculator uses the relationship between molar conductivity, conductivity, and molar concentration. It converts entered values to base SI units before calculating, then converts the result back to the unit you selected.

\Lambda_m = \kappa / c
\kappa = \Lambda_m * c
c = \kappa / \Lambda_m
  • Λm = molar conductivity, usually in S·m²/mol or S·cm²/mol
  • κ = conductivity, usually in S/m, S/cm, or S/ft
  • c = molar concentration, usually in mol/m³, mol/cm³, or mol/ft³

If you leave molar conductivity blank, the calculator divides conductivity by molar concentration. If you leave conductivity blank, it multiplies molar conductivity by molar concentration. If you leave molar concentration blank, it divides conductivity by molar conductivity.

The base unit relationship is:

  • S/m divided by mol/m³ gives S·m²/mol.
  • S·m²/mol multiplied by mol/m³ gives S/m.
  • S/m divided by S·m²/mol gives mol/m³.

Common Unit Conversions for Molar Conductivity Calculations

These are the conversion factors used to bring values into base units before applying the formula.

Quantity Entered Unit Base Unit Multiply By
Molar conductivity S·m²/mol S·m²/mol 1
Molar conductivity S·cm²/mol S·m²/mol 0.0001
Conductivity S/cm S/m 100
Molar concentration mol/cm³ mol/m³ 1,000,000
Molar concentration mol/ft³ mol/m³ 35.3147
If You Know Leave Blank Formula Used
Conductivity and molar concentration Molar conductivity Λm = κ / c
Molar conductivity and molar concentration Conductivity κ = Λmc
Conductivity and molar conductivity Molar concentration c = κ / Λm

Example Calculations

Example 1: Calculate molar conductivity

You have a solution with conductivity of 0.014 S/m and molar concentration of 0.20 mol/m³.

\Lambda_m = 0.014 / 0.20 = 0.070 S*m^2/mol

The molar conductivity is 0.070 S·m²/mol.

Example 2: Calculate conductivity

You have a molar conductivity of 0.012 S·m²/mol and a molar concentration of 50 mol/m³.

\kappa = 0.012 * 50 = 0.600 S/m

The conductivity is 0.600 S/m.

FAQ

What is molar conductivity?

Molar conductivity is the conducting ability of all ions produced by one mole of an electrolyte in solution. It relates the measured conductivity of the solution to its molar concentration. A higher molar conductivity means the ions carry charge more effectively at that concentration.

Why does the calculator use mol/m³ instead of mol/L?

The base SI unit for concentration in this formula is mol/m³. Many chemistry problems use mol/L, also called molarity, but 1 mol/L equals 1000 mol/m³. If your concentration is in mol/L, multiply it by 1000 before entering it as mol/m³.

What happens if concentration is zero?

You cannot calculate molar conductivity by dividing by zero concentration. A zero concentration means there are no moles of solute per volume, so the formula Λm = κ / c cannot be evaluated.