To identify the element indicated by each electron configuration, we can analyze each configuration and match it to the corresponding element:
1. Electron configuration: \(1s^2 2s^2 2p^6\)
This corresponds to the element Neon (Ne). Neon has a complete second shell with 2 electrons in the 1s subshell, 2 electrons in the 2s subshell, and 6 electrons in the 2p subshell.
Chemical symbol: \( \boxed{\text{Ne}} \)
2. Electron configuration: \(1s^2 2s^2 2p^6 3s^2 3p^3\)
This corresponds to the element Phosphorus (P). Phosphorus has a third shell configuration with 2 electrons in the 1s subshell, 2 electrons in the 2s subshell, 6 electrons in the 2p subshell, 2 electrons in the 3s subshell, and 3 electrons in the 3p subshell.
Chemical symbol: \( \boxed{\text{P}} \)
3. Electron configuration: \(1s^2 2s^2 2p^6 3s^2 3p^6 4s^1\)
This corresponds to the element Potassium (K). Potassium has a complete third shell and starts filling the fourth shell with 1 electron in the 4s subshell.
Chemical symbol: \( \boxed{\text{K}} \)
4. Electron configuration: \(1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8\)
This corresponds to the element Nickel (Ni). Nickel has a filled 4s subshell and starts filling the 3d subshell with 8 electrons.
Chemical symbol: \( \boxed{\text{Ni}} \)
5. Electron configuration: \(1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^3\)
This corresponds to the element Niobium (Nb). Niobium has a filled 4p subshell, and starts filling the 4d subshell with 3 electrons in addition to the 2 electrons in the 5s subshell.
Chemical symbol: \( \boxed{\text{Nb}} \)
So, the respective chemical symbols for the given electron configurations are:
[tex]\[
\begin{array}{l}
1s^2 2s^2 2p^6: \boxed{\text{Ne}} \\
1s^2 2s^2 2p^6 3s^2 3p^3: \boxed{\text{P}} \\
1s^2 2s^2 2p^6 3s^2 3p^6 4s^1: \boxed{\text{K}} \\
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8: \boxed{\text{Ni}} \\
1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} 4p^6 5s^2 4d^3: \boxed{\text{Nb}}
\end{array}
\][/tex]
