Question

In the reaction shown below, ____________ acts as a base because ___________. HCO3- + H2O à H3O+ + CO32-

Answer 1

Answer: In the reaction $HCO^{-}_{3} + H_{2}O \rightarrow H_{3}O^{+} + CO^{2-}_{3}$, $H_{2}O$ acts as a base because it has accepted a hydrogen ion or proton.

Explanation:

According to Arrhenius, species which dissociate to give hydrogen ions when dissolved in a solvent like water are called acid.

A species which readily accepts a hydrogen ion or proton is called a base.

For example, $HCO^{-}_{3} + H_{2}O \rightarrow H_{3}O^{+} + CO^{2-}_{3}$

Here, $HCO^{-}_{3}$ is donating hydrogen ion. So, it is an acid whereas $H_{2}O$ is accepting the hydrogen ion. Hence, $H_{2}O$ is a base.

Thus, we can conclude that in the reaction $HCO^{-}_{3} + H_{2}O \rightarrow H_{3}O^{+} + CO^{2-}_{3}$, $H_{2}O$ acts as a base because it has accepted a hydrogen ion or proton.