Chapter 20, Problem 78A

Interpretation Introduction

Interpretation: The reason that $N^{3-}$ , nitride can act as a reducing agent only is to be explained.

Concept introduction: The chemical species that undergo oxidation and loss of electrons are reducing agents.

Answer to Problem 78A

  $N^{3-}$ can acts as an oxidizing agent since it is a stable compound that has accomplished octet. No more electrons are needed for it.

Explanation of Solution

The atomic number of N is 7. And the electronic configuration of N is 2, 5. From the electronic configuration, it is visible that the acceptance of 3 electrons will make nitrogen complete the octet. And also the loss of 3 electrons will make N stable.

The oxidation number of N in nitride, $N^{3-}$ is -3. Nitride is a stable compound, since, it has completed its octet. The further reduction of nitride ions is not stable since it has already completed the octet. Therefore, loss of electrons is only possible to $N^{3-}$ . Therefore it can only act as an oxidizing agent.