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Degree of Dissociation given Ka and Initial Concentration Calculator

Degree of Dissociation Formula:

\[ \alpha = \sqrt{\frac{K_a}{C_0}} \]

mol/m³

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1. What is Degree of Dissociation?

Definition: The Degree of Dissociation is the extent of generating current carrying free ions, which are dissociated from the fraction of solute at a given concentration.

Purpose: It helps chemists understand how much a weak acid dissociates in solution at equilibrium.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ \alpha = \sqrt{\frac{K_a}{C_0}} \]

Where:

Explanation: The square root of the ratio between the acid dissociation constant and initial concentration gives the fraction of molecules that dissociate.

3. Importance of Degree of Dissociation

Details: Understanding dissociation helps predict solution conductivity, pH, and chemical reactivity.

4. Using the Calculator

Tips: Enter the acid dissociation constant (Ka) and initial concentration (C0). Both values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What range is typical for degree of dissociation?
A: For weak acids, α typically ranges from 0.01 to 0.3 (1% to 30% dissociation).

Q2: Why does the formula use a square root?
A: The square root comes from the equilibrium expression for weak acid dissociation.

Q3: When is this approximation valid?
A: When the degree of dissociation is small (α < 0.1 or 10% dissociation).

Q4: How does concentration affect dissociation?
A: Lower concentrations typically result in higher degrees of dissociation (more dissociation).

Q5: What if I get α > 1?
A: The approximation breaks down - use the exact quadratic formula instead.

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