A report on Atom and Proton

Atoms and molecules as depicted in John Dalton's A New System of Chemical Philosophy vol. 1 (1808)
The quark content of a proton. The color assignment of individual quarks is arbitrary, but all three colors must be present. Forces between quarks are mediated by gluons.
The Geiger–Marsden experiment:
Left: Expected results: alpha particles passing through the plum pudding model of the atom with negligible deflection.
Right: Observed results: a small portion of the particles were deflected by the concentrated positive charge of the nucleus.
Ernest Rutherford at the first Solvay Conference, 1911
The Bohr model of the atom, with an electron making instantaneous "quantum leaps" from one orbit to another with gain or loss of energy. This model of electrons in orbits is obsolete.
Proton detected in an isopropanol cloud chamber
The binding energy needed for a nucleon to escape the nucleus, for various isotopes
Protium, the most common isotope of hydrogen, consists of one proton and one electron (it has no neutrons). The term "hydrogen ion" implies that that H-atom has lost its one electron, causing only a proton to remain. Thus, in chemistry, the terms "proton" and "hydrogen ion" (for the protium isotope) are used synonymously
A potential well, showing, according to classical mechanics, the minimum energy V(x) needed to reach each position x. Classically, a particle with energy E is constrained to a range of positions between x1 and x2.
3D views of some hydrogen-like atomic orbitals showing probability density and phase (g orbitals and higher are not shown)
This diagram shows the half-life (T½) of various isotopes with Z protons and N neutrons.
These electron's energy levels (not to scale) are sufficient for ground states of atoms up to cadmium (5s2 4d10) inclusively. Do not forget that even the top of the diagram is lower than an unbound electron state.
An example of absorption lines in a spectrum
Graphic illustrating the formation of a Bose–Einstein condensate
Scanning tunneling microscope image showing the individual atoms making up this gold (100) surface. The surface atoms deviate from the bulk crystal structure and arrange in columns several atoms wide with pits between them (See surface reconstruction).
Periodic table showing the origin of each element. Elements from carbon up to sulfur may be made in small stars by the alpha process. Elements beyond iron are made in large stars with slow neutron capture (s-process). Elements heavier than iron may be made in neutron star mergers or supernovae after the r-process.

One or more protons are present in the nucleus of every atom.

- Proton

The nucleus is made of one or more protons and a number of neutrons.

- Atom
Atoms and molecules as depicted in John Dalton's A New System of Chemical Philosophy vol. 1 (1808)

25 related topics with Alpha

Overall

An explanation of the superscripts and subscripts seen in atomic number notation. Atomic number is the number of protons, and therefore also the total positive charge, in the atomic nucleus.

Atomic number

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Charge number of an atomic nucleus.

Charge number of an atomic nucleus.

An explanation of the superscripts and subscripts seen in atomic number notation. Atomic number is the number of protons, and therefore also the total positive charge, in the atomic nucleus.
The Rutherford–Bohr model of the hydrogen atom or a hydrogen-like ion (Z > 1). In this model it is an essential feature that the photon energy (or frequency) of the electromagnetic radiation emitted (shown) when an electron jumps from one orbital to another be proportional to the mathematical square of atomic charge (Z2). Experimental measurement by Henry Moseley of this radiation for many elements (from ) showed the results as predicted by Bohr. Both the concept of atomic number and the Bohr model were thereby given scientific credence.
Russian chemist Dmitri Mendeleev, creator of the periodic table.
Niels Bohr, creator of the Bohr model.
Henry Moseley in his lab.

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.

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Periodic table

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Tabular display of the chemical elements.

Tabular display of the chemical elements.

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3D views of some hydrogen-like atomic orbitals showing probability density and phase (g orbitals and higher are not shown)
Idealized order of shell-filling (most accurate for n  ≲ 4.)
Trend in atomic radii
Graph of first ionisation energies of the elements in electronvolts (predictions used for elements 105–118)
Trend in electron affinities
Flowing liquid mercury. Its liquid state at room temperature is a result of special relativity.
A periodic table colour-coded to show some commonly used sets of similar elements. The categories and their boundaries differ somewhat between sources. Alkali metals
 Alkaline earth metals
 Lanthanides
 Actinides
 Transition metals Other metals
 Metalloids
 Other nonmetals
 Halogens
 Noble gases
Mendeleev's 1869 periodic table
Mendeleev's 1871 periodic table
Dmitri Mendeleev
Henry Moseley
Periodic table of van den Broek
Glenn T. Seaborg
One possible form of the extended periodic table to element 172, suggested by Finnish chemist Pekka Pyykkö. Deviations from the Madelung order (8s < < 6f < 7d < 8p) begin to appear at elements 139 and 140, though for the most part it continues to hold approximately.
Otto Theodor Benfey's spiral periodic table (1964)
Iron, a metal
Sulfur, a nonmetal
Arsenic, an element often called a semi-metal or metalloid

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.

Force (in units of 10,000 N) between two nucleons as a function of distance as computed from the Reid potential (1968). The spins of the neutron and proton are aligned, and they are in the S angular momentum state. The attractive (negative) force has a maximum at a distance of about 1 fm with a force of about 25,000 N. Particles much closer than a distance of 0.8 fm experience a large repulsive (positive) force. Particles separated by a distance greater than 1 fm are still attracted (Yukawa potential), but the force falls as an exponential function of distance.

Nuclear force

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Force (in units of 10,000 N) between two nucleons as a function of distance as computed from the Reid potential (1968). The spins of the neutron and proton are aligned, and they are in the S angular momentum state. The attractive (negative) force has a maximum at a distance of about 1 fm with a force of about 25,000 N. Particles much closer than a distance of 0.8 fm experience a large repulsive (positive) force. Particles separated by a distance greater than 1 fm are still attracted (Yukawa potential), but the force falls as an exponential function of distance.
Corresponding potential energy (in units of MeV) of two nucleons as a function of distance as computed from the Reid potential. The potential well is a minimum at a distance of about 0.8 fm. With this potential nucleons can become bound with a negative "binding energy."
Comparison between the Nuclear Force and the Coulomb Force.
a - residual strong force (nuclear force), rapidly decreases to insignificance at distances beyond about 2.5 fm,
b - at distances less than ~ 0.7 fm between nucleons centers the nuclear force becomes repulsive,
c - coulomb repulsion force between two protons (over 3 fm force becomes the main),
d - equilibrium position for proton - proton, 
r - radius of a nucleon (a cloud composed of three quarks).
Note: 1 fm = 1E-15 m.
A simplified Feynman diagram of a strong proton–neutron interaction mediated by a virtual neutral pion. Time proceeds from left to right.
An animation of the interaction. The colored double circles are gluons. Anticolors are shown as per [[:File:Quark Anticolours.png|this diagram]] ([[:File: Nulcear Force anim.gif|larger version]]).
The same diagram as that above with the individual quark constituents shown, to illustrate how the fundamental strong interaction gives rise to the nuclear force. Straight lines are quarks, while multi-colored loops are gluons (the carriers of the fundamental force). Other gluons, which bind together the proton, neutron, and pion "in flight", are not shown.

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.

A physicist observes alpha particles from the decay of a polonium source in a cloud chamber

Alpha particle

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A physicist observes alpha particles from the decay of a polonium source in a cloud chamber
Alpha radiation detected in an isopropanol cloud chamber (after injection of an artificial source radon-220).
Example selection of radioactive nuclides with main emitted alpha particle energies plotted against their atomic number. Note that each nuclide has a distinct alpha spectrum.
Alpha radiation consists of helium-4 nucleus and is readily stopped by a sheet of paper. Beta radiation, consisting of electrons, is halted by an aluminium plate. Gamma radiation is eventually absorbed as it penetrates a dense material. Lead is good at absorbing gamma radiation, due to its density.
An alpha particle is deflected by a magnetic field
Dispersing of alpha particles on a thin metal sheet
Energy-loss (Bragg curve) in air for typical alpha particle emitted through radioactive decay.
The trace of a single alpha particle obtained by nuclear physicist Wolfhart Willimczik with his spark chamber specially made for alpha particles.

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.

The nucleus of a helium atom. The two protons have the same charge, but still stay together due to the residual nuclear force

Strong interaction

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The nucleus of a helium atom. The two protons have the same charge, but still stay together due to the residual nuclear force
The fundamental couplings of the strong interaction, from left to right: gluon radiation, gluon splitting and gluon self-coupling.
An animation of the nuclear force (or residual strong force) interaction between a proton and a neutron. The small colored double circles are gluons, which can be seen binding the proton and neutron together. These gluons also hold the quark/antiquark combination called the pion together, and thus help transmit a residual part of the strong force even between colorless hadrons. Anticolors are shown as per [[:File:Quark Anticolors.svg|this diagram]]. For a larger version, click here

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.

Elementary particle

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Elementary particle or fundamental particle is a subatomic particle that is not composed of other particles.

Elementary particle or fundamental particle is a subatomic particle that is not composed of other particles.

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.

An oil painting of a chemist (Ana Kansky, painted by Henrika Šantel in 1932)

Chemistry

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Scientific study of the properties and behavior of matter.

Scientific study of the properties and behavior of matter.

An oil painting of a chemist (Ana Kansky, painted by Henrika Šantel in 1932)
Laboratory, Institute of Biochemistry, University of Cologne in Germany.
Solutions of substances in reagent bottles, including ammonium hydroxide and nitric acid, illuminated in different colors
A diagram of an atom based on the Bohr model
Standard form of the periodic table of chemical elements. The colors represent different categories of elements
Carbon dioxide (CO2), an example of a chemical compound
A ball-and-stick representation of the caffeine molecule (C8H10N4O2).
A 2-D structural formula of a benzene molecule (C6H6)
Diagram showing relationships among the phases and the terms used to describe phase changes.
An animation of the process of ionic bonding between sodium (Na) and chlorine (Cl) to form sodium chloride, or common table salt. Ionic bonding involves one atom taking valence electrons from another (as opposed to sharing, which occurs in covalent bonding)
In the methane molecule (CH4), the carbon atom shares a pair of valence electrons with each of the four hydrogen atoms. Thus, the octet rule is satisfied for C-atom (it has eight electrons in its valence shell) and the duet rule is satisfied for the H-atoms (they have two electrons in their valence shells).
Emission spectrum of iron
During chemical reactions, bonds between atoms break and form, resulting in different substances with different properties. In a blast furnace, iron oxide, a compound, reacts with carbon monoxide to form iron, one of the chemical elements, and carbon dioxide.
The crystal lattice structure of potassium chloride (KCl), a salt which is formed due to the attraction of K+ cations and Cl− anions. Note how the overall charge of the ionic compound is zero.
Hydrogen bromide exists in the gas phase as a diatomic molecule
Democritus' atomist philosophy was later adopted by Epicurus (341–270 BCE).
15th-century artistic impression of Jābir ibn Hayyān (Geber), a Perso-Arab alchemist and pioneer in organic chemistry.
Antoine-Laurent de Lavoisier is considered the "Father of Modern Chemistry".
In his periodic table, Dmitri Mendeleev predicted the existence of 7 new elements, and placed all 60 elements known at the time in their correct places.
Top: Expected results: alpha particles passing through the plum pudding model of the atom undisturbed. 
Bottom: Observed results: a small portion of the particles were deflected, indicating a small, concentrated charge.

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.

Hydrogen atom (center) contains a single proton and a single electron. Removal of the electron gives a cation (left), whereas the addition of an electron gives an anion (right). The hydrogen anion, with its loosely held two-electron cloud, has a larger radius than the neutral atom, which in turn is much larger than the bare proton of the cation. Hydrogen forms the only charge-+1 cation that has no electrons, but even cations that (unlike hydrogen) retain one or more electrons are still smaller than the neutral atoms or molecules from which they are derived.

Ion

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Hydrogen atom (center) contains a single proton and a single electron. Removal of the electron gives a cation (left), whereas the addition of an electron gives an anion (right). The hydrogen anion, with its loosely held two-electron cloud, has a larger radius than the neutral atom, which in turn is much larger than the bare proton of the cation. Hydrogen forms the only charge-+1 cation that has no electrons, but even cations that (unlike hydrogen) retain one or more electrons are still smaller than the neutral atoms or molecules from which they are derived.
Schematic of an ion chamber, showing drift of ions. Electrons drift faster than positive ions due to their much smaller mass.
Avalanche effect between two electrodes. The original ionization event liberates one electron, and each subsequent collision liberates a further electron, so two electrons emerge from each collision: the ionizing electron and the liberated electron.
Equivalent notations for an iron atom (Fe) that lost two electrons, referred to as ferrous.
Mixed Roman numerals and charge notations for the uranyl ion. The oxidation state of the metal is shown as superscripted Roman numerals, whereas the charge of the entire complex is shown by the angle symbol together with the magnitude and sign of the net charge.
An electrostatic potential map of the nitrate ion . The 3-dimensional shell represents a single arbitrary isopotential.

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.

Moseley in 1914

Henry Moseley

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English physicist, whose contribution to the science of physics was the justification from physical laws of the previous empirical and chemical concept of the atomic number.

English physicist, whose contribution to the science of physics was the justification from physical laws of the previous empirical and chemical concept of the atomic number.

Moseley in 1914
Blue plaque erected by the Royal Society of Chemistry on the Townsend Building of Oxford's Clarendon Laboratory, commemorating Moseley's work on X-rays emitted by elements

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.

Combinations of three u, d or s quarks forming baryons with a spin-3⁄2 form the uds baryon decuplet

Baryon

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Type of composite subatomic particle which contains an odd number of valence quarks .

Type of composite subatomic particle which contains an odd number of valence quarks .

Combinations of three u, d or s quarks forming baryons with a spin-3⁄2 form the uds baryon decuplet
Combinations of three u, d or s quarks forming baryons with a spin-1⁄2 form the uds baryon octet

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.