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Ion simulator

Take electrons away or add them, and watch the size change.

SchoolLive

Scientific learning path

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  5. 05ExplainLive
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  7. 07TestBuilding
Explanation mode
Na
Neutral atom166 pm
Na
Na166 pm
Not an ion this element commonly forms.

Description of this simulation

Sodium as a neutral atom: 11 protons and 11 electrons balance exactly. Its covalent radius is 166 pm.

Na

Sodium

Protons
11
Electrons
11
Charge
0
Atomic (covalent) radius
166 pm
Ionic radius
—
Electron configuration
1s2 2s2 2p6 3s1

What this model shows — and what it simplifies

Educational Model

Ionic radii are Shannon effective radii for six-coordinate ions.

Where do we see this in real life?

Water softeners work on ion size and charge: calcium and magnesium ions bind to the resin more tightly than sodium ions do, so they swap places and leave the water.