Build an atom
Add protons, neutrons and electrons, and watch what you have made.
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Scientific learning path
- 01UnderstandLive
- 02ExploreLive
- 03ExperimentLive
- 04ObserveLive
- 05ExplainLive
- 06ApplyLive
- 07TestBuilding
Explanation mode
- Protons1
- Neutrons0
- Electrons1
Protons
Neutrons
Electrons
Try one
Description of this simulation
1 proton makes this Hydrogen. With 0 neutrons the mass number is 1, so this is Hydrogen-1. Electrons balance protons exactly, so the atom is neutral. This isotope is stable.
HHydrogen
- Atomic number
- 1
- Mass number
- 1
- Charge
- 0Neutral atom
- Isotope
- Hydrogen-1
- Electron configuration
- 1s1
- Stability
- Stable
- Natural abundance
- 99.9885%
- Neutron-to-proton ratio
- 0.00
What this model shows — and what it simplifies
Educational ModelThe rings are a shell diagram — a way to count electrons per shell.
Where do we see this in real life?
A smoke alarm contains americium-241 — 95 protons and 146 neutrons. Change the neutron count and you change the half-life, which is exactly why that isotope and not another one sits in the ceiling.