Atom Builder
Add protons, neutrons and electrons and see what you have made: the element, its mass number and charge, whether it is an ion, which isotope it is, and how the electrons fill the Bohr shells. Stability comes from a table of the stable nuclides. For anything else the likely decay is a rule of thumb, and the tool says so.
What you can do
- Every element up to oganesson, with a periodic table to jump to any of them
- Isotope notation, charge and ion names worked out from the three counts
- Bohr shells and the full electron configuration, including ions
- Stable or unstable from a table of the 250 stable nuclides
- Practice questions on counting particles and naming elements