pH Calculator

Calculate pH

pH Value: ?

Step-by-Step Solution

pH = -log₁₀[H⁺]

  1. Enter the hydrogen ion concentration [H⁺] in mol/L.
  2. Apply the formula: pH = -log₁₀[H⁺].
  3. Calculate the pH value using a base-10 logarithm.
  4. The result is the pH of the solution.
Example: If [H⁺] = 0.0001 mol/L, then pH = -log₁₀(0.0001) = 4

Description of the Formula

The pH formula, pH = -log₁₀[H⁺], quantifies the acidity or basicity of a solution. The pH scale ranges from 0 to 14, where values less than 7 indicate acidity, 7 indicates neutrality, and values greater than 7 indicate basicity. The [H⁺] represents the hydrogen ion concentration in moles per liter (mol/L).

Formula Origin

The pH scale was introduced by Søren Peder Lauritz Sørensen in 1909. It is a measure of the relative amount of free hydrogen and hydroxyl ions in water. Solutions with more free hydrogen ions are acidic, whereas those with more hydroxyl ions are basic.

Practice Problems

Problem 1: Calculate the pH of a solution with [H⁺] = 0.001 mol/L.

Problem 2: What is the pH if [H⁺] = 1.0 x 10⁻⁷ mol/L?

Calculation History

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