Full configuration
1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰
In the short form, [Kr] stands for the 36 electrons of krypton, the noble gas before palladium. Only the electrons after it are written out.
Orbital diagram
Outer subshells only. Each box is an orbital; electrons fill singly first (Hund's rule), then pair up with opposite spins.
Why it's an exception
Palladium is the odd one out: both 5s electrons move into 4d to make a full 4d¹⁰ with an empty 5s.
Configuration of palladium ions
| Ion | Configuration | Unpaired | Moment (BM) |
|---|---|---|---|
| Pd²⁺ | [Kr] 4d⁸ | 2 | 2.83 |
Moment is the spin-only magnetic moment μ = √(n(n + 2)) Bohr magnetons, where n is the number of unpaired electrons. Positive ions lose electrons from the outermost shell first, so transition metals lose their 4s or 5s electrons before d.
Nearby elements
| Z | Element | Configuration |
|---|---|---|
| 43 | Technetium | [Kr] 4d⁵ 5s² |
| 44 | Ruthenium | [Kr] 4d⁷ 5s¹ |
| 45 | Rhodium | [Kr] 4d⁸ 5s¹ |
| 47 | Silver | [Kr] 4d¹⁰ 5s¹ |
| 48 | Cadmium | [Kr] 4d¹⁰ 5s² |
| 49 | Indium | [Kr] 4d¹⁰ 5s² 5p¹ |
Questions students ask
What is the electronic configuration of palladium?
[Kr] 4d¹⁰, or in full, 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ 4s² 4p⁶ 4d¹⁰. Palladium has atomic number 46.
How many electrons are in each shell of palladium?
2, 8, 18, 18 (K, L, M, N… shells in order).
How many unpaired electrons does palladium have?
0 in the ground state, so palladium atoms are diamagnetic.
What is the electronic configuration of Pd²⁺?
[Kr] 4d⁸, with 2 unpaired electrons.
Why is palladium an exception?
Palladium is the odd one out: both 5s electrons move into 4d to make a full 4d¹⁰ with an empty 5s.