Views: 667 https //phet.colorado.edu/sims/html/build-an-atom/latest/build-an-atom en.html Build an atom from scratch, using protons, neutrons, and electrons. Test different combinations to produce ions and unstable elements. PhET sims are fun, interactive, research-based simulations of physical phenomena developed … Continue reading https //phet.colorado.edu/sims/html/build-an-atom/latest/build-an-atom en.html