Enter your Analytical Concentration (C), Stoichiometric Acidity (n), and Strong Acid Type into the Strong Acid pH Calculator to find the pH Value of your solution, along with the pOH Value, [H⁺] Concentration, and [OH⁻] Concentration.
pH Value
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pOH Value
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[H⁺] Concentration
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[OH⁻] Concentration
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pH is a measure of acidity or alkalinity of a solution. It's calculated as pH = -log₁₀([H⁺]), where [H⁺] is the hydrogen ion concentration in mol/L.
Strong acids dissociate completely in water, so [H⁺] = n × C, where n is stoichiometric acidity and C is concentration. Weak acids require equilibrium calculations.
Stoichiometric acidity is the number of H⁺ ions each acid molecule can donate. HCl has n=1, H₂SO₄ has n=2, and H₃PO₄ has n=3.
At 25°C, pH + pOH = 14.00. This relationship comes from the water autoionization constant (Kw = 1.0 × 10⁻¹⁴).
The common strong acids are HCl, HNO₃, H₂SO₄, HBr, HI, and HClO₄. These acids completely ionize in aqueous solution.
Yes, pH can be negative for very concentrated strong acid solutions. For example, 10 M HCl has a pH of approximately -1.
These calculations assume complete dissociation, 25°C temperature, and ignore activity effects. They're highly accurate for dilute solutions but less precise for very concentrated solutions.