Find [H⁺] from pH 7
Inntak
pH = 7.00
Úttak
pH = 7.00, pOH = 7.00, [H⁺] = 1.00 × 10^-7 mol/L, [OH⁻] = 1.00 × 10^-7 mol/L
pH Reiknivél (pH, pOH, and concentration conversion)
A simple pH reiknivél to convert H+, pH, and pOH for education and quick svið notes. It helps you check pH calculation, pOH calculation, and hydrogen ion concentration in one place.
See pH / pOH / [H⁺] / [OH⁻] together, with optional formulas and short practical notes.
Three inntak tabs so the starting point is obvious
pH / pOH / [H⁺] / [OH⁻] shown as one fixed set
Formula view, copy, and share URL included
Temperature and activity cautions kept visible
Calculation assumptions
This verkfæri performs a basic conversion from concentration to pH and does not handle activity.
The ion vara of water (pKw) and the neutral point vary with temperature, but this verkfæri uses the basic value pKw = 14.00.
Errors can become larger for concentrated solutions, buffered kerfis, or solutions with high ionic strength.
How to use
- Choose whether you want to start from pH, [H⁺], or pOH.
- Enter a value to calculate pH / pOH / [H⁺] / [OH⁻] immediately.
- Add a temperature note if needed, and adjust significant figures for concentration úttak.
- Turn on Show formulas when you want to see the equation and substitution steps.
- Copy the niðurstaða or share the current setup by URL.
Common examples
Find pH from [H⁺] = 1 × 10^-3
Inntak
[H⁺] = 1e-3 mol/L
Úttak
pH = 3.00, pOH = 11.00
Check the basic side from pOH 5
Inntak
pOH = 5.00
Úttak
pH = 9.00, [OH⁻] = 1.00 × 10^-5 mol/L
Calculation assumptions
- This verkfæri performs a basic conversion from concentration to pH and does not handle activity.
- The ion vara of water (pKw) and the neutral point vary with temperature, but this verkfæri uses the basic value pKw = 14.00.
- Errors can become larger for concentrated solutions, buffered kerfis, or solutions with high ionic strength.
Glossary
pH
A skráarithmic expression of hydrogen ion concentration.
pOH
A skráarithmic expression of hydroxide ion concentration.
pKw
The skráarithmic form of the ion vara of water. Around 25°C, 14 is often used as the basic value.
Activity
An effective concentration term used to describe non-ideal behavior, especially in concentrated or high-ionic-strength kerfis.
Buffer solution
A kerfi that resists pH change when acid or base is added, so it cannot be handled by simple pH-to-concentration conversion alone.
Formulas
pH = -log10([H+])pOH = -log10([OH-])pH + pOH = 14.00[H+] = 10^(-pH)[OH-] = 10^(-pOH)
Algengar spurningar
Does temperature change the niðurstaða?
Strictly speaking, yes. This verkfæri uses the basic assumption pKw = 14.00 and treats temperature as a note only.
Can I use this for buffers?
Not directly. Buffer kerfis need a different model, so a simple pH-to-concentration conversion is not enough.
Is this enough for research work?
Treat it as an estimate. For research or quality control, use actual measurements, calibration standards, and activity-aware methods when needed.
What unit does [H⁺] use here?
This verkfæri assumes mol/L (M).
Is pH + pOH always 14?
Fourteen is a common basic value near 25°C, but pKw changes with temperature. This verkfæri fixes it at 14.00 for basic calculations.
Important notes
- This verkfæri is intended for education and quick svið notes.
- Actual measurements can differ because of temperature, activity, and ionic strength.
- For research or quality control, use a calibrated pH meter and the appropriate corrections for your conditions.
- Do not rely on this basic calculation alone for buffers or highly concentrated kerfis.