The initial state of an electron and a negative charge.	A later state showing the electron is pushed away.
The initial state of an electron and a positive charge.	A later state shows the electron is attracted to the charge.
The polarization of an atom by a nearby positive charge, showing the shift of the electron cloud towards it.	The polarization of an atom by a nearby negative charge, showing the shift of the electron cloud away from it.
When another nucleus is too far away from an atom, it can only polarize it.	When another nucleus is close enough to an atom, the electron is shared by both, forming a covalent bond.
The initial state of a bound electron in a static electric field.	A later state shows the tunnel ionization is nearly completed.

The above images are just some screenshots made from the real model. Click the above button or this link to launch this interactive activity.