pH Calculator
Convert between pH, hydrogen-ion concentration [H+], pOH and hydroxide concentration [OH−] for water at 25 °C.
[H+]
0.001 mol/L
- pH
- 3
- pOH
- 11
- [OH−]
- 1e-11 mol/L
- The solution is
- Acidic
Assumes water at 25 °C, where Kw = 1.0 × 10⁻¹⁴ and pH + pOH = 14.
Show the work
[H+] from pH
[H+] = 10 to the power of −pH
10 to the power of −3 = 0.001 mol/L
How it works
pH = −log₁₀[H+]; pOH = 14 − pH; [OH−] = 1.0 × 10⁻¹⁴ ÷ [H+] (water at 25 °C)
Questions
- How does the pH calculator work?
- pH = −log₁₀[H+]; pOH = 14 − pH; [OH−] = 1.0 × 10⁻¹⁴ ÷ [H+] (water at 25 °C).
- What do I need to enter?
- I know, Value. Optional fields can be left blank.
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