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Caesium atom & ion lab

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

UndergraduateLive

Scientific learning path

  1. 01UnderstandLive
  2. 02ExploreLive
  3. 03ExperimentLive
  4. 04ObserveLive
  5. 05ExplainLive
  6. 06ApplyLive
  7. 07TestLive
Explanation mode
Cs

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 energy375.7 kJ mol⁻¹
Covalent radius244 pm
Electronegativity0.79 Pauling

Lowest first ionization energy of any element measured at 1 atm.

Description of this simulation

Caesium is neutral here: 55 protons are balanced by 55 electrons across shells 2, 8, 18, 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?

Cs

Caesium

Z = 55
Protons
55
Electrons
55
Shells
2 · 8 · 18 · 18 · 8 · 1
Configuration
[Xe] 6s1
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 55 protons, which is what defines Caesium.

Where do we see this in real life?

The electron count and measured properties of Caesium 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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