Chemistry A-Level
Distinguishing capacity from filling order
What Distinguishing capacity from filling order means in Chemistry A-Level, as defined for OCR.
Definition of Distinguishing capacity from filling order
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Reference: OCR
The third and fourth shells are not always filled to their maximum before the next shell begins, because the 4s sub-shell fills before 3d, but the capacity of each shell is still given by 2n².
Topics that use Distinguishing capacity from filling order
- Electron structure (OCR A-Level)
Related terms
- Atomic orbital
- Atomic orbitals
- Cations lose electrons, anions gain electrons
- Electron capacity of s-, p- and d-sub-shells
- Electron configuration
- Fixed number of orbitals per sub-shell
- Ion electron configurations
- Noble-gas shorthand
Using Distinguishing capacity from filling order in the exam
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