The orbital diagram for a chlorine (Cl) atom can be represented by filling its atomic orbitals according to the Aufbau principle, Hund’s rule, and the Pauli exclusion principle.
Chlorine has an atomic number of 17, which means it has 17 electrons. Electrons are filled into orbitals starting from the lowest energy level to the highest. The orbital filling order is:
- 1s
- 2s
- 2p
- 3s
- 3p
The orbital diagram for chlorine can be written as follows:
1s: ↑↓ 2s: ↑↓ 2p: ↑↓ ↑↓ ↑ 3s: ↑↓ 3p: ↑↓ ↑
Here’s how to read it:
- The 1s orbital is filled with 2 electrons.
- The 2s orbital is filled with another 2 electrons.
- The 2p orbitals (three orbitals) are filled with a total of 6 electrons (2 in each of the first two and 2 in one of the p orbitals).
- The 3s orbital is filled with 2 electrons.
- The 3p orbitals have 5 electrons in total, with 2 electrons paired in the first two orbitals and 1 electron in one of the p orbitals (following Hund’s rule).
This arrangement shows that the Cl atom has a stable octet in the outer shell, which is essential for its chemical properties.