The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons (except in the case of hydrogen-1, which is the only stable nuclide with no neutrons). The electrons of an atom are bound to the nucleus by the electromagnetic force. Likewise, a group of atoms can remain bound to each other by chemical bonds based on the same force, forming a molecule. An atom containing an equal number of protons and electrons is electrically neutral, otherwise it is positively or negatively charged and is known as an ion. An atom is classified according to the number of protons and neutrons in its nucleus: the number of protons determines the chemical element, and the number of neutrons determines the isotope of the element.[1]Chemical atoms, which in science now carry the simple name of "atom," are minuscule objects with diameters of a few tenths of a nanometer and tiny masses proportional to the volume implied by these dimensions. Atoms can only be observed individually using special instruments such as the scanning tunneling microscope. Over 99.94% of an atom's mass is concentrated in the nucleus,[note 1] with protons and neutrons having roughly equal mass. Each element has at least one isotope with an unstable nucleus that can undergo radioactive decay. This can result in a transmutation that changes the number of protons or neutrons in a nucleus.[2] Electrons that are bound to atoms possess a set of stable energy levels, or orbitals, and can undergo transitions between them by absorbing or emitting photons that match the energy differences between the levels. The electrons determine the chemical properties of an element, and strongly influence an atom's magnetic properties. The principles of quantum mechanics have been successfully used to model the observed properties of the atom.http://en.wikipedia.org/wiki/Atomic_nucleushttp://en.wikipedia.org/wiki/Atomhttp://hyperphysics.phy-astr.gsu.edu/hbase/particles/proton.html both the proton and the neutrons in the nucleus are commonly denominated nucleons. The mass number A is the total number of nucleons. Thus neutrons. The elemental identify and the chemical properties are basically determinde by the atomic number even if most chemical interactions take place via the interactions of the surrounding electron cloudA = N + ZWhere Z is the number of protons, i.e. the atomic number and N is the number of neutrons. The elemental identify and the chemical properties are basically determined by the atomic number even if most chemical interactions take place via the interactions of the surrounding electron cloud.

In above we know that in atomic nuclei have protn and neutron. According electrostica, a sort charge repulsion so that protons in atomic nuclei, more near the proton with eact other, more big its repulsion force. This case appear question, how can this proton bonding in atomic nuclei?

How can neuton bonding in collected of proton?Kind of nucleus force as follow1. Nucleus force not electric force. In nuclei atom has a electrical force that repulsion force each proton.2. Nuclei force must strong! Atom finger assumed in atom more than 20.0002 = 4 x 108 times tensile force of electron and proton in hydrogen atom.3. Nuclei force is a near force, its mean that this force work when a particle in atom have a near distance with each other.4. Nuclei force doesnt work if the distance very ner of each other

The force that work in atom consist of two kind, are strong force (nuclei force) and repulsion coulomb force. An nucleus or nucleid will stable if if both force balance. This can happen when the number of neutron, N, same or greater that number of proton, Z. If number proton more dominant than number of neutron in nucleus, coulomb force repulsion will dominant so that the nucleus become not stable. Nucleus not stable will gain neutron or release proton for becoming stable.

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