In the following multiple choice tests, we often abbreviate $H_3O^+$ by $H^+$ ( Which is actually false, indeed, $H^+$ is always fully hydrated in water!)

Which of the following species is amphoteric ? i) H+ ii) OH- iii) H2O iv) H3O+

a) iii) alone only b) ii) and iii) only c) iii) and iv) only d) ii), iii) and iv) e) all

For answers, use (possibly several times) the arrows ↑ Down! and ↓ Up! Complete please this question before moving on to the next one!

a) ist correct , $OH^-$ is not amphoteric, because it has hardly any acidic character ( pKa too high )