Created By : Rina Nayak

Reviewed By : Phani Ponnapalli

Last Updated : Apr 03, 2023


Free Ionic Strength Calculator provides the ionic strength for the given concentration and valency. You have to enter the concentration and oxidation of all ions in a chemical solution and hit the calculate button to get the solution ionic strength as result in a fraction of seconds.

Enter concentration(in mol/L) of species separated by comma(,)
Enter the valence/oxidation of the species(separated by comma(,))

Steps to Find Ionic Strength

Below-provided is the simple step by step process to calculate the ionic strength of a solution easily. Go through these rules and obtain the result.

  • Check the concentration, valence of all the ions in a chemical solution.
  • Get the square of the charge of every ion.
  • Multiply every ion concentration with its charge square.
  • Add up the products of all the species.
  • Get half of the sum to know the ionic strength.

Ionic Strength Definition

Ionic strength is the measure of the concentration of ions present in a solution. When ionic compounds are dissolved in water, it dissociates into ions. The main characteristic of the solution with the dissolved ions is the ionic strength.

The ionic strength plays an important role in Debye–Hückel theory. The concept of ionic strength was formulated by Lewis and Randall in 1921. It is based on the dissociation that involves acid, bases and salts in the presence of an aqueous solution.

Ionic Strength Formula

The ionic strength formula computes the sum of each ion's molar concentration multiplied by the valence squared.

Ionic strength formula is I = ½ ∑i=1n cizi2

Where,

I si the ionic strength

c is the molar concentration

z is the valence

Example:

Question: Find the ionic strength of K2SO4.

Answer:

Given solution is K2SO4

Molar concentration of K+ = 2

Molar concentration of SO4-2 = 1

Valence of K+ = 1

Valence of O4-2 = 2

I = ½ ∑i=1n cizi2

Ionic strength formula is I = ½(2(1)² + 1(2)²)

= ½(2 + 4) = 3

Therefore, the ionic strength of K2SO4 is 3.

Chemistrycalc.Com has got concepts like pH, molar concentration, molarity, entropy and many more along with their relevant calculators all one under one roof.

Frequently Asked Questions on Ionic Strength Calculator

1. What is the ionic strength for a 1.0 m NaCl solution?

List the concentrations and valences to reduce confusion.

Na+ = 1.0 M, Cl- = 1.0 M

Ionic strength I = ½ ∑i=1n cizi2

= ½(1 * 1² + 1 * 1²) = 1

Therefore, the ionic strength of NaCl is 1.


2. How to calculate ionic strength?

Multiply the ionic concentration with the square of ion charges. Add all the products and divide the result by 2 to get the ionic strength.


3. What do you mean by ionic strength?

The ionic strength of a solution is defined as the measure of ion concentration in the solution. When ionic compounds are dissolved in water, it dissociates into ions. The characteristic of the solution with the dissolved ions is ionic strength.


4. What is the ionic strength formula?

The ionic strength formula is I = ½ ∑i=1n cizi2.


Ionic Strength Calculator