Ionic Strength Calculator Formula
Understand the math behind the ionic strength calculator. Each variable explained with a worked example.
Formulas Used
Ionic Strength
ionic_strength = 0.5 * (conc_1 * pow(charge_1, 2) + conc_2 * pow(charge_2, 2))Variables
| Variable | Description | Default |
|---|---|---|
conc_1 | Concentration of Ion 1(M) | 0.1 |
charge_1 | Charge of Ion 1 | 2 |
conc_2 | Concentration of Ion 2(M) | 0.2 |
charge_2 | Charge of Ion 2 | 1 |
How It Works
How to Calculate Ionic Strength
Formula
I = 0.5 × Sum(c_i × z_i^2)
Ionic strength measures total charge concentration and affects activity coefficients.
Worked Example
0.1 M CaCl2: 0.1 M Ca2+ and 0.2 M Cl-.
conc_1 = 0.1charge_1 = 2conc_2 = 0.2charge_2 = 1
- 01I = 0.5 × (0.1 × 4 + 0.2 × 1)
- 02I = 0.5 × (0.4 + 0.2)
- 03I = 0.3 M
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Open Ionic Strength Calculator