Elements

Electron configuration of Palladium (Pd)

Read the Palladium electron configuration, noble-gas shorthand, valence shell, orbital filling logic, and the mistakes to avoid when writing Pd. Includes the Pd 4d10 exception — no 5s electrons.

Guide: Guía práctica Read: 5 min Updated: 2026-07-07

Element guide

Electron configuration of Palladium (Pd)

The electron configuration of Palladium is 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10. In shorthand form it is written as [Kr] 4d10.

Use this page to connect the notation with atomic number 46, the d-block, and the unique valence pattern 4d10.

How to write the configuration

Configuration at a glance

Palladium has atomic number 46, so a neutral atom has 46 electrons. The configuration 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10 is unusual — there are NO 5s electrons.

The shorthand [Kr] 4d10 shows that Palladium's valence electrons reside entirely in the 4d subshell. This is the most dramatic s-to-d promotion among period 5 transition metals.

The Palladium exception (extreme)

Palladium has the most unusual electron configuration of any group 10 element. Based on the pattern of Nickel (Ni: [Ar] 3d8 4s2), you would expect Pd to have [Kr] 4d8 5s2. Instead, BOTH 5s electrons have been promoted to the 4d subshell, giving [Kr] 4d10 — a completely filled d-subshell with no s electrons.

This happens because a filled 4d10 subshell is exceptionally stable. The energy gained from completely filling all five d orbitals outweighs the cost of emptying the 5s orbital entirely.

Palladium is unique in this regard. Not even Platinum (Pt: [Xe] 4f14 5d9 6s1) achieves the same complete d10 s0 configuration.

Step-by-step filling walkthrough: 1. Start with atomic number 46. 2. Fill through krypton: 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 (36 electrons). 3. The 5s and 4d orbitals fill with 10 remaining electrons. 4. Ground state result: both 5s electrons promoted to 4d, giving 4d10. 5. Verify: add every superscript and confirm the total equals 46.

Common mistakes

The most common mistake is writing [Kr] 4d8 5s2 following the Ni pattern. Palladium is the extreme case: it has NO 5s electrons. The second mistake is forgetting to count: 2+2+6+2+6+10+2+6+10 = 46.

A third error is assuming that Pd follows the same pattern as Pt or Ni. It does not — Pd is unique in its complete d10 s0 configuration.

Palladium reference table

Item Value
Atomic number 46
Full configuration 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10
Noble-gas notation [Kr] 4d10
Valence clue 4d10
Block d-block

Use the table as a learning reference, then verify advanced oxidation-state questions with your course material.

Before you submit an answer

  • The superscripts add up to 46 for a neutral Palladium atom.
  • The notation follows the filling order used in your course.
  • The last occupied subshell matches the periodic-table block.
  • Any transition-metal or actinide exception is checked against a reference.
  • The shorthand core is a noble gas, not a random previous element.

Common questions

What is the electron configuration of Palladium?

The neutral Palladium atom is written as 1s2 2s2 2p6 3s2 3p6 3d10 4s2 4p6 4d10. The shorthand form is [Kr] 4d10. There are no 5s electrons.

Is Palladium an exception to the Aufbau principle?

Yes, and it is the most extreme case among transition metals. Both 5s electrons are promoted to the 4d subshell, resulting in the only d10 s0 configuration in the periodic table.

How many valence electrons does Palladium have?

Palladium has 10 valence electrons, all in the 4d subshell. The 4d10 shell is completely filled, which contributes to Pd's relative chemical inertness.

How does Palladium's configuration differ from Platinum's?

Pd has [Kr] 4d10 (no s electrons), while Pt has [Xe] 4f14 5d9 6s1. Although both are group 10 elements, their configurations are very different.

Study notes and practice checks

From answer to understanding

Palladium is a precious metal used in catalytic converters, electronics, and hydrogen storage. Its empty 5s orbital and filled 4d10 shell make it unusually resistant to oxidation.

Practice comparison

Compare Palladium (Pd) with Nickel (Ni) and Platinum (Pt). Ni: [Ar] 3d8 4s2, Pd: [Kr] 4d10 (extreme exception), Pt: [Xe] 4f14 5d9 6s1. The trend from Ni (normal d8 s2) to Pd (d10) to Pt (d9 s1) shows that period 5 has the most dramatic exceptions.

Teacher and self-study notes

Pd is frequently tested on exams as the most extreme example of an Aufbau exception. If an exam asks 'which element has no s electrons in its outer shell?', the answer is almost certainly Palladium.

Elena Marquez

Autora de la guia

Elena Marquez

Chemistry educator and study-guide editor

Elena explains electron configurations, orbital diagrams, and periodic trends for learners who need clear steps before memorization. Her guides focus on counting, notation, and common classroom mistakes.

Credenciales: Editorial specialization in introductory chemistry, periodic trends, and student reference material.

Experiencia: More than eight years preparing practical chemistry explainers, worksheets, and reference material for independent learners.

Actualizado: 2026-07-07 Politica editorial Correcciones

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Guides use a repeatable count-and-check method, flag common exceptions, and avoid collecting personal or student data.

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