What is the main difference between electron configuration and orbital notation?

Orbital Notation is more specific on where exactly the electron is placed.

Explanation:

When writing an electron configuration for an atom, rather than writing out the occupation of each and every orbital specifically, you instead lump all the core electrons together and designate it with a symbol of the corresponding noble gas on the Periodic Table.

the arrangement of electrons in the orbitals of an atom or molecule

While Orbital Notation is a visual transformation of the electron configuration. It shows you where each specific electron is placed and what its "spin" is.

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