Ionization energy lab
Strip electrons one at a time and find where the cost jumps.
Scientific learning path
- 01UnderstandLive
- 02ExploreLive
- 03ExperimentLive
- 04ObserveLive
- 05ExplainLive
- 06ApplyLive
- 07TestBuilding
The last removals cost hundreds of times more than the first. On a linear scale the early steps would be invisible.
Data covers hydrogen to calcium.
Description of this simulation
Removing the first electron from Na costs 495.8 kJ/mol. The second removal costs 9.2 times the one before it — a jump that big means the electron is coming out of a filled inner shell, not the outer one. So Na has 1 valence electron.
Na
Sodium
Remove the next electron
What this model shows — and what it simplifies
Educational ModelThese are measured energies for removing an electron from an isolated gaseous atom, one after another.
Where do we see this in real life?
Sodium vapour street lamps work because sodium gives up its single valence electron for relatively little energy. The second electron would cost nine times as much, which is why sodium is only ever Na⁺ and never Na²⁺.