Book question 6A.11 [ENDORSED]

[Lara Almeida 3D]

I'm not sure how to solve this exercise could someone please help me? I say the answers but I wan't able to understand them.

The problem is:

Write the chemical equations of the two proton transfer equilibria that demonstrate the amphiprotic character of (a) HCO3- (b) HPO42-. Identify the conjugate acid–base pairs in each case.

Can we use water as an example of both base and acid?

[Jonathan Sautter 1J]

For this question, you need to write the chemical equation of the compounds when they gain a proton from water (forming their conjugate acid and OH-) and when they donate a proton to water (forming their conjugate base and H3O+). This is used to illustrate the amphiprotic nature of the molecules, meaning they can act as both acids and bases. Water also shows its amphiprotic nature in these equations by forming both (OH- and H3O+). Also note that the equations for amphiprotic molecules only differ in adding or subtracting one H+ atom.

[Kiku Shirakata 2A]

Hello,

Just as Jonathan explained above, water has amphoteric characteristics because it acts as both a Bronsted acid and base. Water also has amphiprotic characteristics because it can act as both a proton (H+) donor and acceptor. Note these slight differences in definition. For example, Al2O3 is an example of having amphoteric characteristics but not amphiprotic characteristics.

Hope this helps!