acids in solution are a source of hydrogen ions, H+. The hydrogen ions are produced when the acid dissociates or breaks down to form ions.
strong acids:
acids completely dissociate into ions in solution. For example, hydrochloric acid is a strong acid. It ionises completely to form hydrogen ions and chloride ions:
HCl(aq) → H+(aq) + Cl-(aq)
nitric acid and sulfuric acid are also strong acids.
weak acids:
acids only partially dissociate in solution. For example, ethanoic acid is a weak acid. It is only partially ionised to form hydrogen ions and ethanoate ions
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