A report on Atom and Proton

For ordinary nuclei, this is equal to the proton number (np) or the number of protons found in the nucleus for every atom of that element.

The smallest constituents of all normal matter are known as atoms.

Atoms consist of a small positively charged nucleus, made of positively charged protons and uncharged neutrons, surrounded by a cloud of negatively charged electrons; the charges cancel out, so atoms are neutral.

The nuclear force (or nucleon–nucleon interaction, residual strong force, or, historically, strong nuclear force) is a force that acts between the protons and neutrons of atoms.

Alpha particles, also called alpha rays or alpha radiation, consist of two protons and two neutrons bound together into a particle identical to a helium-4 nucleus.

When an atom emits an alpha particle in alpha decay, the atom's mass number decreases by four due to the loss of the four nucleons in the alpha particle.

Strong interaction or strong nuclear force is a fundamental interaction that confines quarks into proton, neutron, and other hadron particles.

On a larger scale (of about 1 to 3 femtometer), it is the force (carried by mesons) that binds protons and neutrons (nucleons) together to form the nucleus of an atom.

Ordinary matter is composed of atoms, once presumed to be elementary particles – atomos meaning "unable to be cut" in Greek – although the atom's existence remained controversial until about 1905, as some leading physicists regarded molecules as mathematical illusions, and matter as ultimately composed of energy.

Subatomic constituents of the atom were first identified in the early 1930s; the electron and the proton, along with the photon, the particle of electromagnetic radiation.

It is a natural science that covers the elements that make up matter to the compounds composed of atoms, molecules and ions: their composition, structure, properties, behavior and the changes they undergo during a reaction with other substances.

The nucleus is made up of positively charged protons and uncharged neutrons (together called nucleons), while the electron cloud consists of negatively charged electrons which orbit the nucleus.

An ion is an atom or molecule with a net electrical charge.

The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by convention.

That theory refined Ernest Rutherford's and Antonius van den Broek's model, which proposed that the atom contains in its nucleus a number of positive nuclear charges that is equal to its (atomic) number in the periodic table.

(This was later to be the basis of the Aufbau principle in atomic studies.) As noted by Bohr, Moseley's law provided a reasonably complete experimental set of data that supported the (new from 1911) conception by Ernest Rutherford and Antonius van den Broek of the atom, with a positively charged nucleus surrounded by negatively charged electrons in which the atomic number is understood to be the exact physical number of positive charges (later discovered and called protons) in the central atomic nuclei of the elements.

For example, a proton is made of two up quarks and one down quark; and its corresponding antiparticle, the antiproton, is made of two up antiquarks and one down antiquark.

These particles make up most of the mass of the visible matter in the universe and compose the nucleus of every atom.