Identify a substance that would alter the pH of a solution, but that the Arrhenius’ model would fail to identify appropriately. Explain why you selected this substance.

Answer 1

Pretty much any Lewis acid or Lewis base would alter the pH of a solution but wouldn't be identified to do so by the Arrhenius model. For example, CO₂ (carbon dioxide) is a Lewis acid and would alter the pH of an aqueous solution. This substance was selected because it is one of the more common Lewis acids. Could have chosen BF₃ or any number of other Lewis acids, or bases.