pH Calculator
Calculate pH from hydrogen ion concentration [H+] or find [H+] from pH value. Interactive pH scale visualization from 0 (acidic) to 14 (basic).
Formula: pH = −log₁₀[H⁺]
How to Use the pH Calculator
- Enter the known physical values in the corresponding fields.
- Select the appropriate units if multiple options are available.
- The unknown value is computed instantly from the formula.
- Review the result and the formula explanation below.
Referencia Rápida
| De | A |
|---|---|
| Speed of light | 299,792,458 m/s |
| Gravity (g) | 9.807 m/s² |
| Avogadro's number | 6.022 × 10²³ |
| Boltzmann const. | 1.38 × 10⁻²³ J/K |
| Elementary charge | 1.602 × 10⁻¹⁹ C |
| Planck's const. | 6.626 × 10⁻³⁴ J·s |
Casos de Uso
- •Solving physics homework or exam problems with the correct formula.
- •Verifying experimental measurements and calculations in the lab.
- •Understanding physical relationships between quantities.
- •Quick engineering calculations for design or estimation.
Preguntas Frecuentes
What is pH?
pH is a scale from 0 to 14 that measures how acidic or basic (alkaline) a solution is. A pH of 7 is neutral, below 7 is acidic, and above 7 is basic.
How is pH calculated?
pH = -log₁₀[H⁺], where [H⁺] is the hydrogen ion concentration in mol/L. For example, if [H⁺] = 0.001 mol/L, then pH = 3.
What is pOH?
pOH = -log₁₀[OH⁻] and pH + pOH = 14 at 25°C. You can calculate pOH as 14 - pH.
What are examples of common pH values?
Stomach acid: pH ≈ 1-2; lemon juice: pH ≈ 2; pure water: pH = 7; blood: pH ≈ 7.4; baking soda: pH ≈ 9; bleach: pH ≈ 12.
Is pH temperature-dependent?
Yes. The pH of pure water is 7 only at 25°C. At higher temperatures, the neutral pH decreases slightly. For most practical calculations, 25°C is assumed.