Sure, let's complete the electronic configurations for the elements listed in Table 1.7. Each configuration is determined by filling up the electron orbitals according to the Aufbau principle, which states that electrons occupy the lowest energy orbitals first.
Depending on the atomic number of each element, we determine the subshell electronic configuration. Additionally, we use the appropriate preceding noble gas as a reference point for the electron configuration notation. Here’s the detailed step-by-step process for each of the elements:
### For Calcium (Ca):
- Atomic Number: 20
- The preceding noble gas is Argon ([tex]$[Ar]$[/tex]) with an atomic number of 18.
- Following Argon, we fill the [tex]$4s$[/tex] orbital.
- Electronic Configuration: [tex]$[Ar] 4s^2$[/tex]
### For Magnesium (Mg):
- Atomic Number: 12
- The preceding noble gas is Neon ([tex]$[Ne]$[/tex]) with an atomic number of 10.
- Following Neon, we fill the [tex]$3s$[/tex] orbital.
- Electronic Configuration: [tex]$[Ne] 3s^2$[/tex]
### For Cobalt (Co):
- Atomic Number: 27
- The preceding noble gas is Argon ([tex]$[Ar]$[/tex]) with an atomic number of 18.
- Following Argon, we fill the [tex]$3d$[/tex] and [tex]$4s$[/tex] orbitals.
- Electronic Configuration: [tex]$[Ar] 3d^7 4s^2$[/tex]
### For Zinc (Zn):
- Atomic Number: 30
- The preceding noble gas is Argon ([tex]$[Ar]$[/tex]) with an atomic number of 18.
- Following Argon, we fill the [tex]$3d$[/tex] and [tex]$4s$[/tex] orbitals.
- Electronic Configuration: [tex]$[Ar] 3d^{10} 4s^2$[/tex]
Based on these electronic configurations, the completed table is as follows:
[tex]\[
\begin{array}{|c|c|}
\hline
\text{Elements} & \text{Subshell electronic configuration} \\
\hline
{}_{21} \text{Sc} & {[ \text{Ar} ] 3 d^1 4 s^2} \\
\hline
{}_{20} \text{Ca} & {[ \text{Ar} ] 4 s^2} \\
\hline
{}_{12} \text{Mg} & {[ \text{Ne} ] 3 s^2} \\
\hline
{}_{27} \text{Co} & {[ \text{Ar} ] 3 d^7 4 s^2} \\
\hline
{}_{30} \text{Zn} & {[ \text{Ar} ] 3 d^{10} 4 s^2} \\
\hline
\end{array}
\][/tex]
