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Francium atom & ion lab

Change the electron count of Francium and inspect its charge, shells and reviewed atomic properties.

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Scientific learning path

  1. 01UnderstandLive
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Explanation mode
Fr

Core label represents the fixed nuclear charge; individual neutrons are not inferred from standard atomic weight.

Reviewed atomic properties

Unavailable measurements remain explicitly unavailable.

First ionization energy393 kJ mol⁻¹
Covalent radius260 pm
Electronegativity0.7 Pauling

No stable isotope; the longest-lived, Fr-223, has a half-life of 22 minutes. Melting and boiling points are extrapolated, not measured. Its first ionization energy is HIGHER than caesium’s: relativistic contraction of the 7s orbital pulls the outer electron closer in, so caesium, not francium, is the element easiest to ionize.

Description of this simulation

Francium is neutral here: 87 protons are balanced by 87 electrons across shells 2, 8, 18, 32, 18, 8, 1.

Quick test · 3 questions
1. Which statement is evidence from this simulation?
2. How should you test the effect of one control?
3. Why read the model notes?

Fr

Francium

Z = 87
Protons
87
Electrons
87
Shells
2 · 8 · 18 · 32 · 18 · 8 · 1
Configuration
[Rn] 7s1
Common oxidation states
1
Phase near room conditions
solid

What this model shows — and what it simplifies

Educational Model

The nuclear charge stays fixed at 87 protons, which is what defines Francium.

Where do we see this in real life?

The electron count and measured properties of Francium help determine how it bonds, reacts and is identified in chemical materials.

Explain this result

Scientific review record

Building
Module version
v1 bundled
Published
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Last reviewed
Not yet verified
Academic level
Undergraduate
Reviewer
Not publicly assigned

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