How to Calculate Buffer Capacity (β)
Evaluate buffer resistance using Van Slyke's equation:
Enter Buffer Concentration
Input total buffer species concentration C = [HA] + [A⁻] in mol/L.
Enter Weak Acid pKa
Input negative log dissociation constant pKa of conjugate acid.
Enter Operating pH
Input solution working pH value.
Compute Van Slyke Index
System computes exact buffer capacity β and peak efficiency percentage.
Key Features & Acid-Base Chemistry
Van Slyke Equation Engine
Computes rigorous differential buffer index β = 2.303 × C × (Ka × [H⁺]) / (Ka + [H⁺])².
Peak Efficiency Rating
Determines how close working pH is to peak capacity at pH = pKa (β_max = 0.576 × C).
Biochemical Buffer Prep
Essential for formulating physiological buffers (PBS, Tris, HEPES, acetate).
Analytical Chemistry Guide: Buffer Capacity (β)
Buffer capacity (β) measures the ability of a conjugate acid-base buffer solution to resist changes in pH upon addition of strong acid or strong base:β = 2.303 × C × (Ka × [H⁺]) / (Ka + [H⁺])²The maximum buffer capacity is achieved when pH = pKa, giving βmax = 0.576 × C.
Frequently Asked Questions
?What is the effective pH range for a buffer?
A buffer system is generally considered effective within ±1 pH unit of its pKa (pH range = pKa ± 1.0), where buffer efficiency is at least 33% of maximum.