Cheat Sheets
Concise, accurate references for the concepts behind every structure, designed for quick review.
Valence Electrons
Read an atom's bonding electrons straight off its group, with dot diagrams for every family.
OpenOctet & Duet Rules
Why atoms want eight (or two), shown with real structures and the exceptions that break the rule.
OpenFormal Charge
The formula, the circle-method shortcut, and a before-and-after that shows why lowest charge wins.
OpenVSEPR Geometry Chart
Every AXE class with a 3D sketch, a real example, hybridization, and electron vs molecular shape.
OpenCommon Polyatomic Ions
Organized by family and naming pattern, color-coded by charge, with the classic mnemonic.
OpenResonance
When one Lewis structure isn't enough, and what the real delocalized hybrid means.
OpenElectronegativity & the Pauling Scale
What the number means, the scale for the elements you meet most, and how a difference becomes nonpolar, polar or ionic, with the cutoffs and where they mislead.
OpenPeriodic Trends
Electronegativity, ionization energy, electron affinity, and atomic radius, explained by nuclear charge and shielding instead of 'up and right'.
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