Repulsive electrostatic force among protons

From an electrostatic point of view, it is amazing that positively charged protons can be packed so closely together. Yet many nuclei do not spontaneously decompose, so they must be stable. In the early twentieth century when Rutherford postulated the nuclear model of the atom, scientists were puzzled by such a situation. Physicists have since detected many very short-lived subatomic particles (in addition to protons, neutrons, and electrons) as products of nuclear reactions. Well over 100 have been identified. A discussion of these many particles is beyond the scope of a chemistry text. Furthermore their functions are not entirely understood, but it is now thought that they help to overcome the proton-proton repulsions and to bind nuclear particles (nucleons) together. The attractive forces among nucleons appear to be important over only extremely small distances, about 10 cm. 

An atoms nucleus contains positively charged protons and neutral neutrons. Protons and neutrons are referred to as nucleons. Despite the strong electrostatic repulsion forces among protons, all nucleons remain bound in the dense nucleus because of the strong nuclear force. The strong nuclear force acts on subatomic particles that are extremely close together and overcomes the electrostatic repulsion among protons. 

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