The orbital diagram for an atom of sodium (Na) shows how the electrons are arranged in the atom’s orbitals. Sodium has an atomic number of 11, which means it has 11 electrons.
The electron configuration of sodium is:
1s² 2s² 2p⁶ 3s¹
This means that:
- The first energy level (n=1) has 2 electrons in the 1s orbital.
- The second energy level (n=2) has 2 electrons in the 2s orbital and 6 electrons in the 2p orbitals.
- The third energy level (n=3) has 1 electron in the 3s orbital.
When drawn, the orbital diagram for sodium would look like this:
1s: ↑↓ 2s: ↑↓ 2p: ↑↓ ↑↓ ↑↓ 3s: ↑
In the diagram:
- Each arrow represents an electron, with the direction indicating its spin.
- The 1s, 2s, 2p, and 3s labels identify the specific orbitals where the electrons reside.
This arrangement reflects the Aufbau principle, which states that electrons fill orbitals starting from the lowest energy level to the highest. Understanding the orbital diagram is essential for predicting the chemical behavior of sodium and its interactions with other elements.