Chemistry A-Level
Principal energy levels
What Principal energy levels means in Chemistry A-Level, as defined for OCR.
Definition of Principal energy levels
Check what you remember
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Reference: OCR
These are the levels in an atom that electrons occupy, often called shells, labelled by the principal quantum number n = 1, 2, 3 and so on.
Topics that use Principal energy levels
- 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 Principal energy levels in the exam
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