Defining Orbits in Atoms

Any attempt to determine the path of an electron revolving around the nucleus of an atom run into difficulties. This is mainly due to the uncertainty principle. To determine the path of an electron, one needs to find the location of the electron at a particular instance of time, but any attempt to locate the electron accurately will disturb its momentum largely. As was discussed in the previous section on the microscope, to locate an electron, radiation must be shined on such an electron. The interaction between the radiation and the electron will disturb its momentum in such a way that the electron will be knocked out of its path and thrown into the next orbit. Thus, it is impossible to follow a particle as it moves in an orbit by watching it with a microscope because the quanta of radiation used in observing it will not only send the electron into some other orbit but into one that cannot be predicted and controlled. In other words, according to the uncertainty principle, an electron moving around the nucleus does not have a well-defined path as opposed to a classical view.