Standard solution

The standard solution is a solution in which the concentration of solute in mol dm^-3 or M is known to a high level of accuracy.

Standard solution for acid-alkali titration

If the solution of unknown concentration is acidic, a standard base solution is added to the acid solution until it is neutralized. For example, sulfuric acid (H₂SO₄) is neutralized by potassium hydroxide (KOH).

This also works the other way around. For example, sodium hydroxide (NaOH) is neutralized by hydrochloric acid (HCl).

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• Acid-alkali titration