Use the periodic table to answer this question.

Question

Use the periodic table to answer this question.

Hydrogen selenide (H2Se) reacts with water according to the following equation.
H2Se + H2O → SeH– + H3O+

In three to five sentences, identify the acid, base, conjugate acid, and conjugate base in this reaction. Use patterns in the periodic table to explain why the substances you identified acted as the acid and the base in this reaction.

Answer 1

In this reaction, H2Se acts as the acid and H2O acts as the base. H2Se donates a proton (H+) to H2O, forming the conjugate base SeH- and the conjugate acid H3O+. The acid in a reaction usually donates a proton, while the base accepts a proton. This can be explained by the trends in electronegativity and ionization energy across the periodic table. Hydrogen selenide (H2Se) is a polar compound, with the hydrogen being more electronegative than selenium, allowing it to donate a proton and act as an acid. On the other hand, water (H2O) is less electronegative than hydrogen selenide, making it an effective proton acceptor and thus acting as a base.