Rutherford made the first nuclear reactions by bombarding nitrogen-14 nuclei with alpha particles. However, in his famous gold foil experiment on the scattering of alpha particles by gold, nuclear reactions did not occur. What is the difference between these two experiments? What is necessary for the implementation of nuclear transformation of gold when bombarded with alpha particles? Planetary (or sometimes is called also nuclear) model of atomic structure was proposed by the great English physicist E. Rutherford as a result of a thorough studying the phenomenon of the scattering of alpha particles on the thinnest gold foil. There is no need to give a description of gold foil experiment, as they are well known to anyone. Below we will study a scheme of Rutherford’s experience and see why he was using plates of gold foil to implement the experiment.