Cations as acids

[makenzie2K]

How do we know when a cation will act as an acid in a reaction and predict their relative strength?

[Miriam Sheetz 2B]

Cations are always going to act as acids, but as far as strength, you have to memorize the strong acids: HCl, HNO3, H2SO4, HBr, HI, HClO4, HClO3 . If you know the strong acids, the others are weak acids.

[Arianna Ko 2E]

Small highly charged metal cations can produce acidic solutions. These cations are basically those with a charge of 3+ for example. These small cations can exert the greatest pull on the electrons in surrounding H20 molecules, resulting in a greater number of hydrogen ions to be lost from the water molecules, producing a more acidic solution. The larger Group 1 and 2 cations are too large and have too low of a charge and thus does not have any effect on pulling electrons from the surrounding H20 molecules and will not cause the H20 molecules to release their H protons to form acidic solution.