Chapter 8.2, Problem 8.1BFP

Interpretation Introduction

Interpretation:

The element in which the last electron added has the quantum number $n=2$, $l=1$, $m_l=0$, $m_s=+\frac{1}{2}$ is to be identified. Its electronic configuration and the orbital diagram are to be determined.

Concept introduction:

The quantum numbers provide complete information about the electron.

There are four quantum numbers,namely,principal quantum number, azimuthal quantum number, magnetic quantum numbers, spin quantum number.

1. The highest principal quantum number tells about the shell to which the electron belongs and it is represented by $n$.

2. The azimuthal quantum number tells about the shape of the orbitals and it is represented by $l$.

3. The magnetic quantum number tells about the orientation of orbitals in space and is represented by $m$. The value of $m$ ranges from $l$ to $-l$ including 0. The value of $m$ for the first $p$ orbital is $-l$, the value of $m$ for the second $p$ orbital is 0 and similarly, the value of m for the third $p$ orbital is $+l$.

4. The spin quantum number tells about the spin of the electron and is represented by $m_{\text{s}}$. Its value can either be $+\frac{\text{1}}{\text{2}}$ or $-\frac{\text{1}}{\text{2}}$.