Debye-Huckel Formula:
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Definition: The Debye-Huckel constant (A) describes how ionic activity coefficients depend on ionic strength in dilute solutions.
Purpose: It's essential for understanding electrolyte behavior in solutions and correcting for non-ideal behavior in ionic solutions.
The calculator uses the formula:
Where:
Explanation: The natural log of the activity coefficient is divided by the square of the charge number and the square root of ionic strength.
Details: This constant is crucial for accurate thermodynamic calculations in electrolyte solutions, particularly in chemistry, biology, and environmental science applications.
Tips: Enter the mean activity coefficient (typically between 0 and 1), the charge number (e.g., 1 for Na⁺, 2 for Ca²⁺), and the ionic strength in mol/kg.
Q1: What's a typical value for the Debye-Huckel constant?
A: For water at 25°C, A ≈ 0.509 kg¹ᐟ²/mol¹ᐟ². The value depends on temperature and solvent.
Q2: When is the Debye-Huckel law valid?
A: It's valid for very dilute solutions (typically I < 0.01 mol/kg) where ion-ion interactions are limited.
Q3: How do I find the mean activity coefficient?
A: It can be determined experimentally or estimated from other thermodynamic data.
Q4: What units does the calculator use?
A: The result is in √kg/√mol (square root of kilogram per square root of mole).
Q5: Can I use this for mixed electrolytes?
A: The basic law applies to single electrolytes, but extended versions exist for mixed systems.