The most known design for the Atom was made by Niels Bohr. Bohr was the first to discover that electrons travel in separate orbits around the nucleus and that the number of electrons in the outer orbit determines the properties of an element. He developed the model after studying the way glowing hot hydrogen gives off light.
Protons and Neutrons are subatomic particles in the Nucleus. The electrons in the model are orbitting instead of the electrons scattered all around the place.
Defined an orbital of an atom as: “The region of space that surrounds a nucleus in which two electrons may randomly move.” Using quantum mechanics, chemists can use the electron cloud model to assign electrons to different atomic orbitals. These atomic orbitals are not all spheres. Atomic orbitals also explain the patterns in the periodic table. The electron cloud model were developed in 1925 by Erwin Schrodinger.
Erwin Shrodinger described how electrons move in wave form, and developed the Schrodinger equation which describes how the quantum state of a system changes with time.
Interesting, there is a particle devoid of any electrical charge!
In 1932, the scientist, James Chadwick found the third elementary particle of the atom, the neutron. In 1919 Ernest Rutherford discovered the proton, a positively charged particle contained in the nucleus of the atom. Many were convince that the proton was not the only particle in the nucleus. With that in mind, James went on to find the Neutron.