Chemistry A-Level
Subshell filling across Periods 2 and 3
What Subshell filling across Periods 2 and 3 means in Chemistry A-Level, as defined for OCR.
Definition of Subshell filling across Periods 2 and 3
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Reference: OCR
Each successive element across a period gains one proton and one electron, and the added electron enters the same outer shell until that shell is full.
Topics that use Subshell filling across Periods 2 and 3
- Periodicity (OCR A-Level)
Related terms
- Applying the sequence to specific elements
- atomic radius
- Cations and delocalised electrons
- delocalised electrons
- Distinction from mass number and relative atomic mass
- electrostatic attraction
- First ionisation energy
- Forces broken on melting
Using Subshell filling across Periods 2 and 3 in the exam
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