They both produce H+ right? How do I tell the difference in a reaction?
How come dissolving FeCl3 produces an acidic solution?
Try this for a much longer discussion: http://www.chemguide.co.uk/physical/acidbaseeqia/theories.html
You can look at Bronstead-Lowry as an extension (or complement) to Arrhenius - it handles situations like the one Borek mentioned that Arrhenius does not explicitly cover.
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