#### Which is not amphoteric? Option 1) Option 2) Option 3) Option 4)

As learnt in

Ionization reaction of dibasic acid -

- wherein

are called first and second ionization constant.

Of all the species given,  is the only one that cannot donate a proton and act as an acid. All of these can accept a proton thereby acting as a lease.

Option 1)

This solution is incorrect.

Option 2)

This solution is incorrect.

Option 3)

This solution is incorrect.

Option 4)

This solution is correct.