Ionic Force

`I = 1/2 * \sum_{i} C_i * z_i^2 `
Calculator of the ionic force of an aqueous solution.
Enter data separated by a space.
Powers of 10 : input 2.5*10^-3 or 2.5e-3 for `2.5*10^(-3)`.


This tool calculates the ionic force of an aqueous solution containing n ions. The formula of ionic force is as follows,

`I = 1/2 * \sum_{i=1}^n C_i * z_i^2`

i : the solution contains n ions and i refers to i-th ion of the solution so i = 1, 2 .... , n I : Ionic force of the solution in mol per litre.
Ci : molar concentration of i-th ion in mol per litre.
zi : electronic charge of i-th ion (dimensionless).

Ionic force measures the concentration of the solution in ions and quantifies the interactions between ions and solvent and between ions.

Example of ionic force calculation

Example 1

How to calculate the ionic force of a solution of 1 liter NaCl sodium chloride at 0.02 M ?

We apply the above formula,

[Na+] = 0.02 M and [Cl-] = 0.02 M

I = 0.5* [0.02 * (+1)2 + 0.02 * (−1)2 ] = 0.02 M

Here's the corresponding calculator: I = 0.02 M

Example 2
Let us calculate the ionic force of a 1-liter solution with 42.6 g sodium sulfate Na2SO4and 29.8 g potassium chloride KCl.

In order to apply the above formula, we need to calculate molar masses and molar concentrations.

Molar masses:
Molar mass sodium sulfate (Na2SO4) = 142 g/mol
Molar mass potassium chloride (KCl) = 74.5 g/mol

Molar concentrations:
С (Na2SO4) = 42.6/142 = 0.3 М
С (KCl) = 29.8/74.5 = 0.4 M

Finally, we can calculate the ionic force:
I= 0.5* (2* [Na+] * 12+ 1 * [SO42-] * 22+ 1 * [K+] * 12+ 1 * [Cl-] * 12)
I= 0.5* (2 * 0.3 * 12 + 1 * 0.3 * 22 + 1 * 0.4 * 12 + 1 * 0.4 * 12 )

The corresponding calculator: I = 1.3 M

See also

Conversion of molar concentration units
Molar concentration calculator
Solution and Equilibrium Calculators
Chemistry Calculators