Which is the electron configuration for zinc?

A. [tex]1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8[/tex]
B. [tex]1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^{10}[/tex]
C. [tex]1s^2 2s^2 2p^5 3s^2 3p^6 4s^2 3d^{10}[/tex]
D. [tex]1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10}[/tex]



Answer :

To determine the correct electron configuration for zinc (Zn), let's first identify key information about zinc.

1. Atomic Number: Zinc (Zn) has an atomic number of [tex]\(30\)[/tex]. This means that a neutral zinc atom has 30 electrons.

2. Electron Configuration: We will build the electron configuration step-by-step, ensuring that we follow the order of electron filling according to the Aufbau principle, which dictates the order in which the electron subshells are filled.

- 1s^2: The first shell (n=1) has one s-orbital, which can hold up to 2 electrons. So, the first 2 electrons go into the 1s orbital.
- 2s^2: The second shell (n=2) has one s-orbital, which can hold another 2 electrons. So, the next 2 electrons go into the 2s orbital.
- 2p^6: The second shell (n=2) has three p-orbitals (each can hold 2 electrons), thus can hold a total of 6 electrons. The next 6 electrons go into the 2p orbital.
- 3s^2: The third shell (n=3) has one s-orbital, holding another 2 electrons. The next 2 electrons go into the 3s orbital.
- 3p^6: The third shell (n=3) has three p-orbitals, so it can hold a total of 6 electrons. The next 6 electrons go into the 3p orbital.
- 4s^2: The fourth shell (n=4) has one s-orbital, which can accommodate 2 electrons. The next 2 electrons go into the 4s orbital.
- 3d^{10}: The third shell (n=3) also contains five d-orbitals, which can hold a total of 10 electrons. The final 10 electrons of the zinc atom go into the 3d orbital.

So, the complete electron configuration for zinc (Zn) is:
[tex]\[ 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} \][/tex]

Now, let's compare this configuration with the given options:
1. [tex]\( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8 \)[/tex]
2. [tex]\( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^1 3d^{10} \)[/tex]
3. [tex]\( 1s^2 2s^2 2p^5 3s^2 3p^6 4s^2 3d^{10} \)[/tex]
4. [tex]\( 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} \)[/tex]

The correct configuration that matches our detailed step-by-step electron filling process is:

[tex]\[ 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^{10} \][/tex]

Therefore, the correct electron configuration for zinc is:

[tex]\[ \boxed{4} \][/tex]