Chemistry A-Level
Subshell filling order
What Subshell filling order means in Chemistry A-Level, as defined for OCR.
Definition of Subshell filling order
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Reference: OCR
Subshells are filled in order of increasing energy, and orbitals of equal energy fill singly before pairing, each orbital holding at most two electrons.
Topics that use Subshell filling order
- Electron structure (OCR A-Level)
Related terms
- Atomic orbital
- Atomic orbitals
- Cations lose electrons, anions gain electrons
- Distinguishing capacity from filling order
- Electron capacity of s-, p- and d-sub-shells
- Electron configuration
- Fixed number of orbitals per sub-shell
- Ion electron configurations
Using Subshell filling order in the exam
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