1. What Is Ka?

The acid dissociation constant (K_a) is a quantitative measure of the strength of an acid in solution. It represents the equilibrium constant for the dissociation reaction of a weak acid and indicates how completely an acid donates protons in aqueous solution.

2. How Does The Calculator Work?

The calculator uses the acid dissociation constant formula:

Where:

• \( K_a \) — Acid dissociation constant (M)
• \( [H^+] \) — Hydrogen ion concentration (M)
• \( [A^-] \) — Conjugate base concentration (M)
• \( [HA] \) — Weak acid concentration (M)

Explanation: The equation describes the equilibrium between a weak acid and its dissociation products in aqueous solution. Higher K_a values indicate stronger acids.

3. Importance Of Ka Calculation

Details: Ka values are essential for understanding acid strength, predicting reaction outcomes, calculating pH of weak acid solutions, and designing buffer systems in chemistry and biochemistry.

4. Using The Calculator

Tips: Enter all concentrations in molarity (M). Ensure values are positive and measured at equilibrium conditions. The calculator provides the acid dissociation constant based on the equilibrium concentrations.

5. Frequently Asked Questions (FAQ)

Q1: What does a high Ka value indicate?
A: Higher Ka values indicate stronger acids that dissociate more completely in aqueous solution.

Q2: How is Ka related to pKa?
A: pKa = -log₁₀(Ka). Lower pKa values correspond to stronger acids.

Q3: What are typical Ka values for common acids?
A: Strong acids have Ka > 1, weak acids have Ka < 1. For example, acetic acid Ka ≈ 1.8×10^-5, hydrochloric acid Ka ≈ 10⁷.

Q4: Does temperature affect Ka values?
A: Yes, Ka values are temperature-dependent as dissociation is an equilibrium process affected by thermal energy.

Q5: Can Ka be used for polyprotic acids?
A: Yes, polyprotic acids have multiple Ka values (Ka1, Ka2, etc.) for each dissociation step.