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About this tool
Interactive logarithmic pH scale visualizer with hydronium ion concentration, common household substances, and buffer concepts.
The pH Scale Visualizer turns any pH between 0 and 14 into the two numbers behind it — hydronium concentration from pH = -log₁₀[H⁺], and hydroxide concentration from the water constraint [H⁺][OH⁻] = 10⁻¹⁴ at 25 °C — and shows both in scientific notation as you drag the slider. Eleven household benchmarks from battery acid at pH 0 to drain cleaner at pH 14 snap the slider to a known value so the abstract number has something concrete attached. It is aimed at students meeting the logarithmic scale for the first time, and at anyone who needs to see why one pH unit is a tenfold change rather than a small step.
Open pH Scale Visualizer on AltFTool — it loads instantly in your browser.
Drag the 'pH Level' slider across 0 to 14 in 0.1 steps, or press a Substance Preset such as Lemon Juice 2.0, Human Blood 7.4 or Bleach 13.0.
The pH Spectrum Bar pointer moves and the reading is classified Strongly Acidic, Weakly Acidic, Neutral, Weakly Alkaline or Strongly Alkaline.
Read the hydronium and hydroxide concentrations in mol/L in exponential form under 'Aqueous Ion Data'; 'Reset' returns the slider to pH 7.0.
Every position on the slider reports [H⁺] and [OH⁻] together in exponential form, so the inverse relationship between them is visible rather than described.
Eleven presets place vinegar, milk, baking soda, soap and bleach at their approximate pH, which makes a bare value like 8.5 mean something.
The reading is classified as strongly acidic below pH 3, weakly acidic below 6.5, neutral through the middle, weakly alkaline above 7.5 and strongly alkaline above 11.
pH = -log₁₀[H⁺], where [H⁺] is the hydrogen (hydronium) ion concentration in moles per litre. Inverting it gives [H⁺] = 10⁻ᵖᴴ, which is exactly what this tool computes for every slider position.
Because in pure water at 25 °C the self-ionisation constant is Kw = 10⁻¹⁴, so [H⁺] and [OH⁻] are each 10⁻⁷ mol/L — equal, which is what neutral means. Kw rises with temperature, so the neutral point drifts slightly below 7 in hot water even though the solution is still neutral.
One hundred times. Each whole pH unit is a factor of ten in hydrogen ion concentration, so two units is 10 × 10: pH 3 holds 1.0e-3 mol/L of H⁺ against 1.0e-5 mol/L at pH 5.
Yes. The 0–14 range is a convention that covers dilute aqueous solutions, but very concentrated strong acids can measure below 0 and concentrated hydroxides above 14, because the definition -log₁₀[H⁺] itself has no hard limits. This visualizer covers the standard 0–14 span in 0.1 steps.