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pH Formula

\( pH \;=\;  log_{10}{H^+}\)     (pH)
Symbol English Metric
\( pH \) = pH - \(dimensionless\)
\( H^+ \) = Concentration of Hydrogen Ions in Moles per Liter - \(mol\;/\;L\)

The pH scale indicates the degree of acidity or alkalinity of a solution.  Definition of pH is the logarithm of the reciprocal of the hydrogen-ion \((H^+)\) concentration.  Scale range is usually 0 to 14 where the midpoint is 7.0.  When the pH is 7.0, the fluid is said to be neutral.  Higher values denote alkalinity; lower values denote acidity.  When pH is 0, the solution is the most acidic.  When the pH is 14, the solution is most basic.

pH Interpretation
Low ph (pH 0 - < 3)  -  Strong acid, highly acidic (e.g., hydrochloric acid)
Low ph (pH 3 - < 7)  -  Weak acid, mildly acidic (e.g., vinegar, soda)
pH (pH = 7)  -  Neutral, neither acidic nor basic (e.g., pure water)
High pH (ph > 7 - 11)  -  Weak base, mildly basic (e.g., baking soda)
High pH (ph > 11 - 14)  - Strong base, highly basic (e.g., bleach, lye)

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