Get pH, pOH, [H⁺], and [OH⁻] at 25 °C from either hydrogen-ion concentration or pH.
| pH | – |
| pOH | – |
| [H+] (M) | – |
| [OH−] (M) | – |
Use this calculator for aqueous acid–base at room temperature when you know either [H⁺] or pH and want the rest of the water quartet.
The calculation is pH = −log₁₀[H⁺], pOH = 14 − pH, [OH⁻] = 10⁻¹⁴ / [H⁺]. Activity is treated as concentration. Kw is taken as 1×10⁻¹⁴ (25 °C).
This is not a buffer: use the Buffer calculator for HA/A⁻. It does not correct Kw for other temperatures.
From: Start from molar [H⁺] or from a pH reading.
[H+] (M) or pH: If from [H⁺], type mol/L (0.001 for 10⁻³ M). If from pH, type the pH (7 for neutral).
pH: −log₁₀ of the hydrogen-ion concentration.
pOH: 14 − pH at 25 °C.
[H+] (M): Hydrogen-ion concentration in mol/L, scientific notation.
[OH−] (M): Hydroxide-ion concentration in mol/L, scientific notation.
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