Periodic Trends Explorer

Explore periodic trends including atomic radius, ionic radius, ionization energy, electron affinity, and electronegativity across periods and down groups. Understand how effective nuclear charge (Zeff) and shielding explain why atomic radius decreases across a period but increases down a group, why ionization energy increases across a period, and how these trends predict chemical reactivity and bonding behavior.

PERIODIC TRENDS

Trends like atomic radius and ionization energy are driven by Zeff and shielding.

CORE FORMULAS

Zeff

AP EXAM CONNECTION

Unit: Unit 1: Atomic Structure
Learning Objective: SAP-2.A

COMMON MISCONCEPTIONS

Explaining trends using position only.

KEY TAKEAWAYS

Zeff increases across a period.

DEEP DIVE: RELATED CONCEPTS

ELECTRON CONFIGURATION

Electrons fill orbitals following the Aufbau Principle, Pauli Exclusion Principle, and Hund's Rule....

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