Lewis but not Bronsted-Lowry acid-base reaction

[TT0]

Homework Statement

Homework Equations

The Attempt at a Solution

A lewis acid donates a electron pair while a bronsted-lowry acid accepts a proton. So I need to cancel out all the ones that has proton exchanges. They are B, C, D and E. However, in A, it isn't really an acid base reaction but a solubility equation.

In B the cyanide ion accepts a proton.
In C the ammonia accepts a proton.
In D the water accepts a proton
In E the hydroxide accepts a proton.

Clearly, one of these isn't true so where was my thinking wrong?

Cheers!

 

[Asim Riaz]

Your thinking was not wrong. All of the reactions you listed are acid-base reactions, and all involve the transfer of a proton from one species to another. A is not an acid-base reaction but is a solubility reaction, which involves the dissolution of an ionic compound in water.