Many Metal Cations Produce Aqueous Solutions That Have a PH

Many metal cations produce aqueous solutions that have a pH different from 7. Which one of the following statements A-D about this phenomenon is not correct?

A) For a given metal, the cation with the higher oxidation number will produce more acidic solution, for example, Fe³⁺(aq) is more acidic than Fe²⁺(aq) .
B) The Lewis acidity of the cation is a good measure of its ability to produce an acidic solution.
C) Small highly charged main group metal cations, such as Al³⁺, produce acidic aqueous solutions.
D) Alkali metal cations, such as Na⁺and K⁺, have a negligible effect on the pH of a solution.
E) Statements A-D are all correct.