Practice question · True or false
A concentrated solution of a weak acid can have a lower pH than a dilute solution of a strong acid.
Hints
- Strength and concentration are independent variables.
- Enough of a partially ionising acid can out-acidify a very small amount of a fully ionising one.
Show the answer
True
Why
True, 5 M acetic acid has a far lower pH than 0.001 M hydrochloric acid. Strength fixes the fraction that ionises; concentration fixes how much is there to ionise, and either can dominate.
Practise Acids, Bases and pH
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More questions on Acids, Bases and pH
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