Chemistry A-Level
Period 3 trend
What Period 3 trend means in Chemistry A-Level, as defined for AQA.
Definition of Period 3 trend
Check what you remember
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Reference: AQA
Values rise overall as nuclear charge increases while shielding stays similar, but there are two dips.
Topics that use Period 3 trend
- Electron configuration (AQA A-Level)
Related terms
- 4s before 3d
- First ionisation energy
- Group 2 trend
- ion configurations
- ionisation equations
- orbital capacities
- sub-shell filling order
Using Period 3 trend in the exam
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