This interactive, scaffolded activity allows students to build an atom within the framework of a newer orbital model. It opens with an explanation of why the Bohr model is incorrect and provides an analogy for understanding orbitals that is simple enough for grades 8-9. As the activity progresses, students build atoms and ions by adding or removing protons, electrons, and neutrons. As changes are made, the model displays the atomic number, net charge, and isotope symbol. Try the "Add an Electron" page to build electrons around a boron nucleus and see how electrons align from lower-to-higher energy. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology. The Concord Consortium develops deeply digital learning innovations for science, mathematics, and engineering. The models are all freely accessible. Users may register for additional free access to capture data and store student work products.

This interactive activity helps learners visualize the role of electrons in the formation of ionic and covalent chemical bonds. Students explore different types of chemical bonds by first viewing a single hydrogen atom in an electric field model. Next, students use sliders to change the electronegativity between two atoms -- a model to help them understand why some atoms are attracted. Finally, students experiment in making their own models: non-polar covalent, polar covalent, and ionic bonds. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology.

In this interactive activity, learners explore factors that cause atoms to form (or break) bonds with each other. The first simulation depicts a box containing 12 identical atoms. Using a slider to add heat, students can see the influence of temperature on formation of diatomic bonds. Simulations #2 and #3 introduce learners to reactions involving two types of atoms. Which atom forms a diatomic molecule more easily, and why? The activity concludes as students explore paired atoms (molecules). In this simulation they compare the amount of energy needed to break the molecular bonds to the energy needed to form the bonds. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology.

In this interactive activity, learners build computer models of atoms by adding or removing electrons, protons, and neutrons. It presents the orbital model of an atom: a nucleus consisting of protons and neutrons with electrons surrounding it in regions of high probability called orbitals. Guided tasks are provided, such as constructing a lithium atom and a carbon-12 atom in the fewest possible steps. The activity concludes with a model for building a charged hydrogen atom (an ion). Within each task, students take snapshots of their work product and answer probative questions. This item is part of the Concord Consortium, a nonprofit research and development organization dedicated to transforming education through technology.