Question

What is the distribution of electrons in nitrogen atoms?
A. $\left( {2,4} \right)$
B. $\left( {2,5} \right)$
C. $\left( {2,6} \right)$
D. $(2,5)$

Answer 1

Hint: Nitrogen is the seventh element with an atomic number $7$ and as atomic number tells the number of electrons thus nitrogen has a total of $7$ electrons. In writing the electron configuration for Nitrogen the first two electrons will go in the ${1^{st}}$ orbital. Since $1s$ can only hold two electrons the next $2$ electrons for $N$ goes in the $2s$ orbital. The remaining three electrons will go in the $2p$ orbital.

Complete step by step answer: The total number of electrons present in a Nitrogen atom is $7$.
The distributions of electrons in Nitrogen atom is given by
First orbit or $K$ shell $ = 2\left( {2{n^2} = 2 \times {1^2} = 2} \right)$
Second orbit or $L$ shell = $5$ $(7-2=5)$
Thus the electron distribution of Nitrogen is $(2,5)$ So, the correct answer is (B).
The configuration notation for Nitrogen $N$ provides an easy way for scientists to write and communicate how electrons are arranged around the nucleus of the Nitrogen atom. This makes it easiest to understand and predict how atoms will interact to form chemical bonds.

Additional Information: Chemists write electron configurations to describe and communicate the arrangement of electrons around the nucleus of atoms. This rotation aids in predicting how atoms will join together to form chemical bonds and their behaviour.
Nitrogen reacts with various other elements and forms compounds. For example, Ammonia with the formula $NH_{3}$ is formed when three hydrogen atoms share their electrons with the nitrogen atoms as nitrogen requires three electrons to complete its outermost octet to achieve the nearest noble gas configuration and hydrogen requires two electrons to achieve noble gas configuration, so they both combine and form a covalent bond by sharing three pairs of electrons.

Note: According to the laws of quantum mechanics, for system with only one electron, a level of energy is associated with each electron configuration and in certain conditions, electrons are able to move from one configuration to another by the emission or absorption of quantum of energy in the form of a photon. Energy of an electron depends on the shell in which it is placed. Lower shells electrons have lower energy as compared to electrons with higher shells.