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chemistry / Atomic & Molecular / free

Periodic Trends

Change nuclear pull and shielding to see the periodic table become a set of patterns.

Follow the cause1 / 3

Inner electrons shield. Outer electrons feel less than the full nuclear charge because inner electrons partially screen the nucleus.

periodic trend modelZᵉᶠᶠ = 4.0
Focus the idea
Effective nuclear charge organizes periodic trendsAn atom has 8 protons, 4 shielding units, and 2 occupied shells. Effective nuclear charge is 4.0; relative radius is 0.90 and ionization signal is 8.00.Z = 8shield 4relative radiusionization signal 8.0
effective charge4.0
relative radius0.90
ionization8.00
electronegativity1.20

The nucleus pulls with an effective charge of 4.0 after shielding is accounted for.

Periodic trends are not isolated memorization rules. They emerge from nuclear charge, shielding, and distance competing to control the outer electrons.

04 / PRACTICE
0 / 3 checked

Answer from the model, then use the explanation to connect the particle picture to the chemical rule.

CHECK 1 / 3

What remains after shielding reduces the full nuclear pull?