AP Chemistry / Unit 1: Atomic Structure and Properties
1.7 Periodic Trends
Notes
- Atomic radius: decreases across a period (more protons), increases down a group (more shells).
- Ionization energy: increases across, decreases down.
- Electronegativity: increases across, decreases down (F is highest).
Practice
Which atom is largest?
Down and to the left.
First ionization energy is highest for:
Right side of period 3.
Radius decreases across a period because:
Greater effective nuclear charge.
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