1) Which of the following is not amphiprotic?

Question

H20, NH4^+^, HSO4^-^, H2PO4^-^, all choices are amphiprotic.

I think that all of these are amphiprotic. I know for sure that H20 and H2PO4^-^ are.

2) The ion HPO4^-^ has both a conjugate base as well as a conjugate acid. The conjugate base of this ion is 1 while the conjugate acid is 2.

The question wants to know what the base and acid would be.

PO4^3-^ would be the base because you take the H away and add 1 to the exponent and the acid would be H2PO4^-^ .

Would you agree with my answers?

Answer 1

I agree with 2.
For #1, is NH4^+?
NH4^+ ==> NH3 + H^+ in which it donates a proton. Is that possible?
NH4^+ + H^+ ==> NH4^2+ in which it accepts a proton. Is that possible?