A report on Helium and Chemical element

The chemical elements ordered in the periodic table

Sir William Ramsay, the discoverer of terrestrial helium

$Estimated distribution of dark matter and dark energy in the universe. Only the fraction of the mass and energy in the universe labeled "atoms" is composed of chemical elements.$

The cleveite sample from which Ramsay first purified helium

Periodic table showing the cosmogenic origin of each element in the Big Bang, or in large or small stars. Small stars can produce certain elements up to sulfur, by the alpha process. Supernovae are needed to produce "heavy" elements (those beyond iron and nickel) rapidly by neutron buildup, in the r-process. Certain large stars slowly produce other elements heavier than iron, in the s-process; these may then be blown into space in the off-gassing of planetary nebulae

Historical marker, denoting a massive helium find near Dexter, Kansas

Abundances of the chemical elements in the Solar System. Hydrogen and helium are most common, from the Big Bang. The next three elements (Li, Be, B) are rare because they are poorly synthesized in the Big Bang and also in stars. The two general trends in the remaining stellar-produced elements are: (1) an alternation of abundance in elements as they have even or odd atomic numbers (the Oddo-Harkins rule), and (2) a general decrease in abundance as elements become heavier. Iron is especially common because it represents the minimum energy nuclide that can be made by fusion of helium in supernovae.

The helium atom. Depicted are the nucleus (pink) and the electron cloud distribution (black). The nucleus (upper right) in helium-4 is in reality spherically symmetric and closely resembles the electron cloud, although for more complicated nuclei this is not always the case.

Mendeleev's 1869 periodic table: An experiment on a system of elements. Based on their atomic weights and chemical similarities.

Binding energy per nucleon of common isotopes. The binding energy per particle of helium-4 is significantly larger than all nearby nuclides.

Helium discharge tube shaped like the element's atomic symbol

Liquefied helium. This helium is not only liquid, but has been cooled to the point of superfluidity. The drop of liquid at the bottom of the glass represents helium spontaneously escaping from the container over the side, to empty out of the container. The energy to drive this process is supplied by the potential energy of the falling helium.

Unlike ordinary liquids, helium II will creep along surfaces in order to reach an equal level; after a short while, the levels in the two containers will equalize. The Rollin film also covers the interior of the larger container; if it were not sealed, the helium II would creep out and escape.

Structure of the helium hydride ion, HHe+

Structure of the suspected fluoroheliate anion, OHeF−

The largest single use of liquid helium is to cool the superconducting magnets in modern MRI scanners.

A dual chamber helium leak detection machine

Helium (from ἥλιος) is a chemical element with the symbol He and atomic number 2.

- Helium

The lightest chemical elements are hydrogen and helium, both created by Big Bang nucleosynthesis during the first 20 minutes of the universe in a ratio of around 3:1 by mass (or 12:1 by number of atoms), along with tiny traces of the next two elements, lithium and beryllium.

- Chemical element

19 related topics with Alpha

Nitrogen

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The shapes of the five orbitals occupied in nitrogen. The two colours show the phase or sign of the wave function in each region. From left to right: 1s, 2s (cutaway to show internal structure), 2px, 2py, 2pz.

Table of nuclides (Segrè chart) from carbon to fluorine (including nitrogen). Orange indicates proton emission (nuclides outside the proton drip line); pink for positron emission (inverse beta decay); black for stable nuclides; blue for electron emission (beta decay); and violet for neutron emission (nuclides outside the neutron drip line). Proton number increases going up the vertical axis and neutron number going to the right on the horizontal axis.

Molecular orbital diagram of dinitrogen molecule, N2. There are five bonding orbitals and two antibonding orbitals (marked with an asterisk; orbitals involving the inner 1s electrons not shown), giving a total bond order of three.

Solid nitrogen on the plains of Sputnik Planitia on Pluto next to water ice mountains

Structure of [Ru(NH3)5(N2)]2+ (pentaamine(dinitrogen)ruthenium(II)), the first dinitrogen complex to be discovered

Mesomeric structures of borazine, (–BH–NH–)3

Standard reduction potentials for nitrogen-containing species. Top diagram shows potentials at pH 0; bottom diagram shows potentials at pH 14.

Nitrogen dioxide at −196 °C, 0 °C, 23 °C, 35 °C, and 50 °C. converts to colourless dinitrogen tetroxide at low temperatures, and reverts to at higher temperatures.

Fuming nitric acid contaminated with yellow nitrogen dioxide

Schematic representation of the flow of nitrogen compounds through a land environment

A container vehicle carrying liquid nitrogen.

Nitrogen is the chemical element with the symbol N and atomic number 7.

(The light noble gases, helium, neon, and argon, would presumably also be more electronegative, and in fact are on the Allen scale.) Following periodic trends, its single-bond covalent radius of 71 pm is smaller than those of boron (84 pm) and carbon (76 pm), while it is larger than those of oxygen (66 pm) and fluorine (57 pm).

Periodic table

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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.)

Graph of first ionisation energies of the elements in electronvolts (predictions used for elements 105–118)

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

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)

Arsenic, an element often called a semi-metal or metalloid

The periodic table, also known as the periodic table of the (chemical) elements, is a tabular display of the chemical elements.

Hydrogen is the element with atomic number 1; helium, atomic number 2; lithium, atomic number 3; and so on.

Joseph Priestley is usually given priority in the discovery.

Oxygen

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Antoine Lavoisier discredited the phlogiston theory.

Robert H. Goddard and a liquid oxygen-gasoline rocket

An experiment setup for preparation of oxygen in academic laboratories

Orbital diagram, after Barrett (2002), showing the participating atomic orbitals from each oxygen atom, the molecular orbitals that result from their overlap, and the aufbau filling of the orbitals with the 12 electrons, 6 from each O atom, beginning from the lowest-energy orbitals, and resulting in covalent double-bond character from filled orbitals (and cancellation of the contributions of the pairs of σ and σ* and π and π* orbital pairs).

Liquid oxygen, temporarily suspended in a magnet owing to its paramagnetism

Space-filling model representation of dioxygen (O2) molecule

Late in a massive star's life, 16O concentrates in the O-shell, 17O in the H-shell and 18O in the He-shell.

500 million years of climate change vs. 18O

Photosynthesis splits water to liberate and fixes into sugar in what is called a Calvin cycle.

build-up in Earth's atmosphere: 1) no produced; 2) produced, but absorbed in oceans & seabed rock; 3) starts to gas out of the oceans, but is absorbed by land surfaces and formation of ozone layer; 4–5) sinks filled and the gas accumulates

Hofmann electrolysis apparatus used in electrolysis of water.

Oxygen and MAPP gas compressed-gas cylinders with regulators

An oxygen concentrator in an emphysema patient's house

Low pressure pure is used in space suits.

Most commercially produced is used to smelt and/or decarburize iron.

Water is the most familiar oxygen compound.

Oxides, such as iron oxide or rust, form when oxygen combines with other elements.

The interior of the Apollo 1 Command Module. Pure at higher than normal pressure and a spark led to a fire and the loss of the Apollo 1 crew.

Oxygen is the chemical element with the symbol O and atomic number 8.

Oxygen is Earth's most abundant element, and after hydrogen and helium, it is the third-most abundant element in the universe.

Helium was first detected in the Sun due to its characteristic spectral lines.

Noble gas

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This is a plot of ionization potential versus atomic number. The noble gases, which are labeled, have the largest ionization potential for each period.

Neon, like all noble gases, has a full valence shell. Noble gases have eight electrons in their outermost shell, except in the case of helium, which has two.

Structure of, one of the first noble gas compounds to be discovered

An endohedral fullerene compound containing a noble gas atom

Bonding in according to the 3-center-4-electron bond model

Liquid helium is used to cool superconducting magnets in modern MRI scanners

15,000-watt xenon short-arc lamp used in IMAX projectors

The noble gases (historically also the inert gases; sometimes referred to as aerogens ) make up a class of chemical elements with similar properties; under standard conditions, they are all odorless, colorless, monatomic gases with very low chemical reactivity.

The six naturally occurring noble gases are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and the radioactive radon (Rn).

Atom

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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.

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.

The binding energy needed for a nucleon to escape the nucleus, for various isotopes

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.

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.

An atom is the smallest unit of ordinary matter that forms a chemical element.

Helium was discovered in this way in the spectrum of the Sun 23 years before it was found on Earth.

Drifting smoke particles indicate the movement of the surrounding gas.

Gas

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One of the four fundamental states of matter .

Random motion of gas particles results in diffusion.

21 April 1990 eruption of Mount Redoubt, Alaska, illustrating real gases not in thermodynamic equilibrium.

Satellite view of weather pattern in vicinity of Robinson Crusoe Islands on 15 September 1999, shows a turbulent cloud pattern called a Kármán vortex street

$Delta wing in wind tunnel. The shadows form as the indices of refraction change within the gas as it compresses on the leading edge of this wing.$

A pure gas may be made up of individual atoms (e.g. a noble gas like neon), elemental molecules made from one type of atom (e.g. oxygen), or compound molecules made from a variety of atoms (e.g. carbon dioxide).

When grouped together with the monatomic noble gases – helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn) – these gases are referred to as "elemental gases".

Hydrogen

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Depiction of a hydrogen atom with size of central proton shown, and the atomic diameter shown as about twice the Bohr model radius (image not to scale)

Hydrogen gas is colorless and transparent, here contained in a glass ampoule.

Phase diagram of hydrogen. The temperature and pressure scales are logarithmic, so one unit corresponds to a 10x change. The left edge corresponds to 105 Pa, which is about atmospheric pressure.

Hydrogen emission spectrum lines in the visible range. These are the four visible lines of the Balmer series

NGC 604, a giant region of ionized hydrogen in the Triangulum Galaxy

Hydrogen is the chemical element with the symbol H and atomic number 1.

Regular passenger service resumed in the 1920s and the discovery of helium reserves in the United States promised increased safety, but the U.S. government refused to sell the gas for this purpose.

Argon

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A: test-tube, B: dilute alkali, C: U-shaped glass tube, D: platinum electrode

Captioned "Argon", caricature of Lord Rayleigh in Vanity Fair, 1899

Space-filling model of argon fluorohydride

Cylinders containing argon gas for use in extinguishing fire without damaging server equipment

A sample of caesium is packed under argon to avoid reactions with air

Gloveboxes are often filled with argon, which recirculates over scrubbers to maintain an oxygen-, nitrogen-, and moisture-free atmosphere

Argon gas-discharge lamp forming the symbol for argon "Ar"

Argon is a chemical element with the symbol Ar and atomic number 18.

The other noble gases (except helium) are produced this way as well, but argon is the most plentiful by far.

Lithium

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Lithium ingots with a thin layer of black nitride tarnish

Lithium is about as common as chlorine in the Earth's upper continental crust, on a per-atom basis.

Nova Centauri 2013 is the first in which evidence of lithium has been found.

Johan August Arfwedson is credited with the discovery of lithium in 1817

Hexameric structure of the n-butyllithium fragment in a crystal

Scatter plots of lithium grade and tonnage for selected world deposits, as of 2017

Lithium use in flares and pyrotechnics is due to its rose-red flame.

The launch of a torpedo using lithium as fuel

Lithium deuteride was used as fuel in the Castle Bravo nuclear device.

Estimates of global lithium uses in 2011 (picture) and 2019 (numbers below)
Ceramics and glass (18%)
Batteries (65%)
Lubricating greases (5%)
Continuous casting (3%)
Air treatment (1%)
Polymers
Primary aluminum production
Pharmaceuticals
Other (5%)

Lithium (from λίθος) is a chemical element with the symbol Li and atomic number 3.

The transmutation of lithium atoms to helium in 1932 was the first fully man-made nuclear reaction, and lithium deuteride serves as a fusion fuel in staged thermonuclear weapons.

Neon

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The first evidence for isotopes of a stable element was provided in 1913 by experiments on neon plasma. In the bottom right corner of J. J. Thomson's photographic plate are the separate impact marks for the two isotopes neon-20 and neon-22.

Neon is a chemical element with the symbol Ne and atomic number 10.

Although neon is a very common element in the universe and solar system (it is fifth in cosmic abundance after hydrogen, helium, oxygen and carbon), it is rare on Earth.