Chapter 19.5, Problem 44SP

a.

Interpretation Introduction

Interpretation : The equation when acid is added to a solution that contains ${\text{HPO}}_{\text{4}}^{\text{2}-}$ is to be written.

Concept Introduction : Acids are substances that contain hydrogen and ionize to produce hydrogen ions $\left({\text{H}}^{\text{+}}\right)$ in an aqueous solution.

Answer to Problem 44SP

The equation when acid is added to a solution that contains ${\text{HPO}}_{\text{4}}^{\text{2}-}$ is given below:

  ${\text{HPO}}_{\text{4}}^{\text{2}-}\left(aq\right)+{\text{H}}^{\text{+}}\left(aq\right)\to {\text{H}}_{\text{2}}{\text{PO}}_4^{-}\left(aq\right)$

Explanation of Solution

  ${\text{H}}_{\text{2}}{\text{PO}}_4^{-}$ is a conjugate base which accepts hydrogen ions.

The acid when added to a solution containing ${\text{HPO}}_{\text{4}}^{\text{2}-}$

giving the following chemical reaction:

  ${\text{HPO}}_{\text{4}}^{\text{2}-}\left(aq\right)+{\text{H}}^{\text{+}}\left(aq\right)\to {\text{H}}_{\text{2}}{\text{PO}}_4^{-}\left(aq\right)$

Hydrogen ions reacts with ${\text{HPO}}_{\text{4}}^{\text{2}-}$ to give ${\text{H}}_{\text{2}}{\text{PO}}_4^{-}$ ions.

b.

Interpretation Introduction

Interpretation : The equation when base is added to a solution that contains ${\text{H}}_2{\text{PO}}_{\text{4}}^{-}$ is to be written.

Concept Introduction : Bases are substances that ionize in aqueous solutions to produce hydroxide ions $\left({\text{OH}}^{-}\right)$ .

Answer to Problem 44SP

The equation when acid is added to a solution that contains ${\text{H}}_2{\text{PO}}_{\text{4}}^{-}$ is given below:

  ${\text{HPO}}_{\text{4}}^{-}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)\to {\text{HPO}}_4^{2-}\left(aq\right)+{\text{H}}_{\text{2}}\text{O}\left(l\right)$

Explanation of Solution

  ${\text{H}}_2{\text{PO}}_{\text{4}}^{-}$ is a conjugate acid which release hydrogen ion.

The base when added to a solution containing ${\text{H}}_2{\text{PO}}_{\text{4}}^{-}$

giving the following chemical reaction:

  ${\text{HPO}}_{\text{4}}^{-}\left(aq\right)+{\text{OH}}^{-}\left(aq\right)\to {\text{HPO}}_4^{2-}\left(aq\right)+{\text{H}}_{\text{2}}\text{O}\left(l\right)$

Hydroxide ions reacts with ${\text{H}}_2{\text{PO}}_{\text{4}}^{-}$ to give ${\text{HPO}}_4^{2-}$ ions.