What is the electron configuration of a nitride ion N3-?
The Correct Answer and Explanation is :
The electron configuration of a nitride ion (N³⁻) is 1s² 2s² 2p⁶.
Explanation
To understand the electron configuration of the nitride ion, we first need to analyze the nitrogen atom itself. Nitrogen (N) has an atomic number of 7, which means it has 7 protons and, in its neutral state, 7 electrons. The electron configuration for a neutral nitrogen atom can be written as:
- 1s² 2s² 2p³
This configuration indicates that nitrogen has two electrons in the first energy level (1s) and five electrons in the second energy level (2s and 2p).
When nitrogen gains three electrons to form a nitride ion (N³⁻), it achieves a more stable electronic arrangement, resembling the nearest noble gas, neon (Ne). The addition of three electrons fills the 2p orbital, leading to the following configuration:
- 1s² 2s² 2p⁶
This configuration reflects that the nitride ion has a total of 10 electrons. Here’s a breakdown of the filling of the orbitals:
- 1s Orbital: The first two electrons fill the 1s orbital completely.
- 2s Orbital: The next two electrons fill the 2s orbital completely.
- 2p Orbital: The three additional electrons occupy the 2p orbital, bringing the total in that subshell to six (2s² and 2p⁶).
The resulting electron configuration (1s² 2s² 2p⁶) indicates that the nitride ion is isoelectronic with neon, which is a stable noble gas. This stability is a driving force behind the formation of ions: atoms tend to gain or lose electrons to achieve a noble gas electron configuration. Thus, the nitride ion’s configuration signifies its full outer shell, contributing to its stability and the overall behavior of nitrogen in chemical reactions.