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Ph calculator
pH Calculator
Precise pH profiling for strong/weak acids and bases with visual scale guidance and calculation transparency.
Input
Input chemistry
About the Ph calculator
Calculate the pH of strong and weak acids and bases from their concentration.
How to use the Ph calculator
- Choose the Calculation mode: strong acid, strong base, weak acid, weak base, or from [HβΊ] or [OHβ»].
- Enter the Concentration and its Units (and Ka / Kb for weak acids and bases).
- Press Calculate pH.
Formula and method
pH = βlogββ[HβΊ] and pH + pOH = 14 at 25 Β°C.
Worked example
0.01 M hydrochloric acid (a strong acid) has [HβΊ] = 0.01, so the pH is 2.
Tips
- pH below 7 is acidic, 7 is neutral and above 7 is basic.
- Each pH unit is a tenfold change in acidity.
Frequently Asked Questions
Strong acids ionise completely in water. Weak acids only ionise partially, so you need Ka.