Activity Coefficient Calculator
Calculate the activity coefficient (gamma) of an ion in an aqueous solution using Debye-Hückel theory.
Calculation Parameters
Adjust the values below.
Calculated Result
Expert Tip
Ensure units are correctly formatted (e.g. Kelvin for gas temperatures and liters for volumes) to get chemically accurate outputs.
How this Calculator Works
This calculator allows you to solve Activity Coefficient problems dynamically. Adjust the input parameters using the sliders or selection menu below:
- Ion Charge (z) (Range: 1 to 4, Default: 1)
- Ionic Strength (I, mol/L) (Range: 0.0001 to 0.1000, Default: 0.0100)
The results are computed instantly and updated in the results panel on the right.
Formula & Methodology
Where:
- Ion Charge: Parameter value.
- Ionic Strength: Parameter value.
Step-by-Step Calculation Example
To calculate Activity Coefficient manually, follow these steps:
- Identify the input parameters. For example:
- Ion Charge (z) = 1
- Ionic Strength (I, mol/L) = 0.0100
- Apply the formula:
log10(γ) = -0.509 * z² * (√I / (1 + √I))
- Verify the calculated value which is updated instantly in the results panel on the right.
Frequently Asked Questions
What is an activity coefficient (γ)? ▼
The activity coefficient measures deviation of a real solution from ideal thermodynamic behavior: a = γ × C.
What is the Debye-Hückel limiting law equation? ▼
log10(γ) = -A × |z+ × z-| × √I, where A ≈ 0.509 at 25°C in water and I is ionic strength.
When does the activity coefficient approach 1.0? ▼
The activity coefficient approaches 1.0 in infinitely dilute aqueous solutions.