He Element

2/14/2022by admin
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Iron-56 is particularly common, since it is the most stable element that can easily be made from alpha particles (being a product of decay of radioactive nickel-56, ultimately made from 14 helium nuclei). Elements heavier than iron are made in energy-absorbing processes in large stars, and their abundance in the universe (and on Earth. List of elements Atomic Number Name Symbol Group Period Number Block State at. STP Occurrence Description 1 Hydrogen H 1 1 s Gas Primordials Non-metal 2 Helium He 18 1 s Gas Primordial Noble gas 3 Lithium Li 1 2 s Solid Primordial Alkali metal 4 Beryllium Be 2 2 s Solid Primordial Alkaline earth metal 5 Boron B 13 2 p Solid Primordial Metalloid 6. The only hope for mankind is the Fifth Element, who comes to Earth every five thousand years to protect the humans with four stones of the four elements: fire, water, Earth and air. A Mondoshawan spacecraft is bringing The Fifth Element back to Earth but it is destroyed by the evil Mangalores.

Helium is a colorless, odorless, tasteless chemical element, one of the noble gases of the periodic table of elements. Its boiling and melting points are the lowest among the elements; except in extreme conditions, it exists only as a gas. The second most abundant element in the universe, significant amounts are found on Earth only in natural gas. It is used in cryogenics, in deep-sea breathing systems, for inflating balloons, and as a protective gas for many purposes. Helium is not toxic and has no biological effect.

hydrogen – helium


Name, Symbol, NumberHelium, He, 2
Atomic weight4.002602
Chemical seriesNoble gases
Group, Period, Block18 (VIIIA), 1, p
Density (0°C, 1 atm)0.179 g/L
Thermal data
Melting point (at 26 atm)0.95 K (-272.2°C)
Boiling point4.22 K (-268.93°C)
Specific heat capacity5193 J/(kg*K)]]
Thermal conductivity0.152 W/(m*K)]]
Heat of vaporization0.0845 kJ/mol
Heat of fusion5230 J/mol
Electronic data
Electron configuration1s2
Electrons per shell2
1st ionization potential2372.3 kJ/mol
2nd ionization potential5250.5 kJ/mol
Steric data
Covalent radius32 pm
van der Waals radius140 pm
Molar volume21.0 ×10-6 m3/mol
Crystal structurehexagonal
isoabundancehalf-lifeDMDE MeVDP
3He0.000137%Stable with 1 neutron
4He99.999863%Stable with 2 neutrons
6Hesynthetic806.7 ms0003²-3.5086Li
All conditions STP except where noted.


Helium was first detected in 1868 as a bright yellow line in the spectrum of the chromosphere of the Sun, by French astronomer Pierre Janssen during a solar eclipse in India. The same year, English astronomer Norman Lockyer also observed a previously unknown yellow line in the solar spectrum and concluded that it was caused by an element unknown on Earth. He and English chemist Edward Frankland named the element with the Greek word for the Sun, helios. In 1895, British chemist William Ramsay isolated helium on Earth by treating cleveite with mineral acids. These samples were identified as helium by Lockyer and British physicist William Crookes. It was independently isolated from cleveite the same year by Swedish chemists Per Teodor Cleve and Nils Langlet.

In 1905, American chemists Hamilton Cady and David McFarland discovered that helium could be extracted from natural gas. In 1907, Ernest Rutherford and Thomas Royds demonstrated that an alpha particle is a helium nucleus. Helium was first liquefied by Dutch physicist Heike Kamerlingh Onnes in 1908 by cooling the gas to less than one kelvin. It was first solidified in 1926 by his student Willem Hendrik Keesom. In 1938, Russian physicist Pyotr Leonidovich Kapitsa discovered that helium-4 has almost no viscosity at temperatures near absolute zero, a phenomenon now called superfluidity. In 1972, the same phenomenon was observed in helium-3 by American physicists Douglas D. Osheroff, David M. Lee, and Robert C. Richardson.

Under standard temperature and pressure, helium exists only as a monatomic gas. It solidifies only under great pressure, the variation of which can drastically change the volume of the solid. Below its boiling point of 4.21 kelvin and above the lambda point 2.1768 kelvin, the isotope helium-4 exists in a normal liquid state, called helium I. Below the lambda point, it begins toexhibit unusual characteristics, in a state called helium II. Less is known about such properties in the isotope helium-3.

Helium II

Helium II exhibits characteristics of two distinct fluids, one a normal, viscous liquid and the other a superfluid apparently without internal friction. It has a mobile, rapid flow through even the smallest of capillaries and, in the fountain effect, can rise over the rim of a containment vessel in a thin film that appears unaffected by gravity. In addition, its thermal conductivity is greater than that of any other known substance. When introduced, heat will rapidly propagate through the substance in waves, a phenomenon called second sound.


Helium is chemically unreactive under all normal conditions. With electric glow discharge or electron bombardment, however, helium can form compounds with tungsten, iodine, fluorine, sulfur and phosphorus.


Although there are six known isotopes of helium, only helium-3 and helium-4 are stable. The others, radioactive, rapidly decay into other substances. The most common isotope, helium-4, is produced by alpha decay from heavier radioactive elements; its nucleus is an alpha particle. It is an unusually stable nucleus because its nucleons are arranged into complete shells. There is only a trace amount of helium-3 on Earth, produced from the beta decay of tritium.


Helium is the second most abundant element in the known universe after hydrogen and constitutes nearly a quarter of the mass of the universe. It is concentrated in the stars, where it is formed from hydrogen by the nuclear fusion of the proton-proton chain reaction and CNO cycle. According to the Big Bang model of the early development of the universe, the vast majority of helium was formed in the first three minutes after the Big Bang.

However, the concentration of helium in the Earth's atmosphere is only 1 part in 200,000, largely because most helium in the Earth's atmosphere escapes into space due to its inertness and low mass. All considerable helium on Earth is a result of radioactive decay. The decay product is found in minerals of uranium and thorium, including cleveites, pitchblende, carnotite, monazite and beryl. There are also small amounts in mineral springs, volcanic gas, meteoric iron. The greatest concentrations on the planet are in natural gas, from which most commercial helium is derived. The principal source in the world is the natural gas wells of the American states of Texas, Oklahoma, and Kansas.


Helium can be synthesized by bombardment of lithium or boron with high-velocity protons.


Because of its low density, helium is the gas of choice to fill airships such as the iconic Goodyear blimp.

Pressurized helium is commercially available, extracted from natural gas.

Helium is used for many purposes:

  • Because it is lighter than air, airships and balloons are inflated with helium for lift. Helium is advantageous in airships because it is not flammable and has 92.64% of the lifting power of the alternative hydrogen.
  • The voice of a person who has inhaled helium becomes temporarily high-pitched, because the speed of sound in helium is nearly thrice that in air, with a corresponding increase in the resonant frequencies of the larynx. Although this is a novel amusement, it can be lethally dangerous with concentrated helium.
  • Trimix, an atmosphere of helium, oxygen, and nitrogen, is used in deep-sea breathing systems to reduce the risk of nitrogen narcosis and oxygen toxicity at high pressures.
  • Because of its extremely low melting and boiling points, helium is used as a coolant in magnetic resonance imaging, nuclear reactors, superconducting magnets, and cryogenics.
  • Because it is inert, helium is used as a protective gas in growing silicon and germanium crystals, in titanium and zirconium production, in arc welding, and in gas chromatography.
  • Helium used to pressurize liquid fuel rockets.
  • Helium is used in supersonic wind tunnels.
  • The gain medium of the helium-neon laser is a mixture of helium and neon.

External links

  • WebElements: Helium(http://www.webelements.com/webelements/elements/text/He/key.html)
  • EnvironmentalChemistry.com – Helium(http://environmentalchemistry.com/yogi/periodic/He.html)
  • It's Elemental – Helium(http://education.jlab.org/itselemental/ele002.html)
  • Hoax: Helium Causes Death (CIAC Hoaxbusters)(http://hoaxbusters.ciac.org/HBUrbanMyths.shtml#helium)
From Simple English Wikipedia, the free encyclopedia


This is a list of elements by atomic number with symbol.

Images For He Element

List of elements




BlockState at


2HeliumHe181sGasPrimordialNoble gas
3LithiumLi12sSolidPrimordialAlkali metal
4BerylliumBe22sSolidPrimordialAlkaline earth metal
10NeonNe182pGasPrimordialNoble gas
11SodiumNa13sSolidPrimordialAlkali metal
12MagnesiumMg23sSolidPrimordialAlkaline earth metal
18ArgonAr183pGasPrimordialNoble gas
19PotassiumK14sSolidPrimordialAlkali metal
20CalciumCa24sSolidPrimordialAlkaline earth metal
21ScandiumSc34dSolidPrimordialTransition metal
22TitaniumTi44dSolidPrimordialTransition metal
23VanadiumV54dSolidPrimordialTransition metal
24ChromiumCr64dSolidPrimordialTransition metal
25ManganeseMn74dSolidPrimordialTransition metal
26IronFe84dSolidPrimordialTransition metal
27CobaltCo94dSolidPrimordialTransition metal
28NickelNi104dSolidPrimordialTransition metal
29CopperCu114dSolidPrimordialTransition metal
30ZincZn124dSolidPrimordialTransition metal
36KryptonKr184pGasPrimordialNoble gas
37RubidiumRb15sSolidPrimordialAlkali metal
38StrontiumSr25sSolidPrimordialAlkaline earth metal
39YttriumY35dSolidPrimordialTransition metal
40ZirconiumZr45dSolidPrimordialTransition metal
41NiobiumNb55dSolidPrimordialTransition metal
42MolybdenumMo65dSolidPrimordialTransition metal
43TechnetiumTc75dSolidTransientTransition metal
44RutheniumRu85dSolidPrimordialTransition metal
45RhodiumRh95dSolidPrimordialTransition metal
46PalladiumPd105dSolidPrimordialTransition metal
47SilverAg115dSolidPrimordialTransition metal
48CadmiumCd125dSolidPrimordialTransition metal
54XenonXe185pGasPrimordialNoble gas
55CaesiumCs16sSolidPrimordialAlkali metal
56BariumBa26sSolidPrimordialAlkaline earth metal
72HafniumHf46dSolidPrimordialTransition metal
73TantalumTa56dSolidPrimordialTransition metal
74TungstenW66dSolidPrimordialTransition metal
75RheniumRe76dSolidPrimordialTransition metal
76OsmiumOs86dSolidPrimordialTransition metal
77IridiumIr96dSolidPrimordialTransition metal
78PlatinumPt106dSolidPrimordialTransition metal
79GoldAu116dSolidPrimordialTransition metal
80MercuryHg126dLiquidPrimordialTransition metal
86RadonRn186pGasTransientNoble gas
87FranciumFr17sSolidTransientAlkali metal
88RadiumRa27sSolidTransientAlkaline earth metal




SyntheticTransition metal
105DubniumDb57dSyntheticTransition metal
106SeaborgiumSg67dSyntheticTransition metal
107BohriumBh77dSyntheticTransition metal
108HassiumHs87dSyntheticTransition metal
112CoperniciumCn127dSyntheticTransition metal

Second list[changechange source]

Chemical symNameOrigin of symbolAtomic No.Atomic massDensity (near r.t.)Melting pointBoiling pointYear of discoveryDiscoverer
AcActinium89227,0278 g/mol10,07 g/cm31047 °C3197 °C1899Debierne
AgSilverLatinArgentum47107,8682 g/mol10,49 g/cm3961,9 °C2212 °Cprehistoricunknown
AlAluminium1326,981539 g/mol2,70 g/cm3660,5 °C2467 °C1825Oersted
AmAmericium95243,0614 g/mol13,67 g/cm3994 °C2607 °C1944Seaborg
ArArgon1839,948 g/mol1,66 g/l-189,4 °C-185,9 °C1894Ramsay and Rayleigh
AsArsenic3374,92159 g/mol5,72 g/cm3613 °C613 (Subl.) °Cca. 1250Albertus Magnus
AtAstatine85209,9871 g/mol7 g/cm3302 °C337 °C1940Corson and MacKenzie
AuGoldLatin Aurum79196,96654 g/mol19,32 g/cm31064,4 °C2940 °Cprehistoricunknown
BBoron510,811 g/mol2,46 g/cm32300 °C2550 °C1808Davy and Gay-Lussac
BaBarium56137,327 g/mol3,65 g/cm3725 °C1640 °C1808Davy
BeBeryllium49,012182 g/mol1,85 g/cm31278 °C2970 °C1797Vauqueli
BiBismuth83208,98037 g/mol9,80 g/cm3271,4 °C1560 °C1540Agricola
BkBerkelium97247,0703 g/mol13,25 g/cm3986 °C2627 °C1949Seaborg
BrBromine3579,904 g/mol3,14 g/cm3-7,3 °C58,8 °C1826Balard
CCarbon612,011 g/mol3,51 g/cm33550 °C4827 °Cprehistoricunknown
CaCalcium2040,078 g/mol1,54 g/cm3839 °C1487 °C1808Davy
CdCadmium48112,411 g/mol8,64 g/cm3321 °C765 °C1817Stromeyer and Hermann
CeCerium58140,115 g/mol6,77 g/cm3798 °C3257 °C1803von Hisinger and Berzelius
CfCalifornium98251,0796 g/mol15,1 g/cm3900 °C1472 °C1950Seaborg
ClChlorine1735,4527 g/mol2,95 g/l-34,6 °C-101 °C1774Scheele
CmCurium96247,0703 g/mol13,51 g/cm31340 °C3110 °C1944Seaborg
CnCopernicium112277 g/mol1996Society for Heavy Ion Research
CoCobalt2758,9332 g/mol8,89 g/cm31495 °C2870 °C1735Brandt
CrChromium2451,9961 g/mol7,14 g/cm31857 °C2482 °C1797Vauquelin
CsCaesium55132,90543 g/mol1,90 g/cm328,4 °C690 °C1860Kirchhoff and Bunsen
CuCopperLatin Cuprum2963,546 g/mol8,92 g/cm31083,5 °C2595 °Cprehistoricunknown
DbDubnium105262,1138 g/mol1967/70Flerow oder Ghiorso
DsDarmstadtium110269 g/mol1994Society for Heavy Ion Research
DyDysprosium66162,5 g/mol8,56 g/cm31409 °C2335 °C1886Lecoq de Boisbaudran
ErErbium68167,26 g/mol9,05 g/cm31522 °C2510 °C1842Mosander
EsEinsteinium99252,0829 g/mol860 °C1952Seaborg
EuEuropium63151,965 g/mol5,25 g/cm3822 °C1597 °C1901Demaçay
FFluorine918,9984032 g/mol1,58 g/l-219,6 °C-188,1 °C1886Moissan
FeIronLatin Ferrum2655,847 g/mol7,87 g/cm31535 °C2750 °Cprehistoricunknown
FmFermium100257,0951 g/mol1952Seaborg
FrFrancium87223,0197 g/mol27 °C677 °C1939Perey
GaGallium3169,723 g/mol5,91 g/cm329,8 °C2403 °C1875Lecoq de Boiskaudran
GdGadolinium64157,25 g/mol7,89 g/cm31311 °C3233 °C1880de Marignac
GeGermanium3272,61 g/mol5,32 g/cm3937,4 °C2830 °C1886Winkler
HHydrogen11,00794 g/mol0,084 g/l-259,1 °C-252,9 °C1766Cavendish
HeHelium24,002602 g/mol0,17 g/l-272,2 °C-268,9 °C1895Ramsay and Cleve
HfHafnium72178,49 g/mol13,31 g/cm32150 °C5400 °C1923Coster and vón Hevesy
HgMercuryLatin Hydragyrum - quicksilver80200,59 g/mol13,55 g/cm3-38,9 °C356,6 °Cprehistoricunknown
HoHolmium67164,93032 g/mol8,78 g/cm31470 °C2720 °C1878Soret
HsHassium108265 g/mol1984Society for Heavy Ion Research
IIodine53126,90447 g/mol4,94 g/cm3113,5 °C184,4 °C1811Courtois
InIndium49114,82 g/mol7,31 g/cm3156,2 °C2080 °C1863Reich and Richter
IrIridium77192,22 g/mol22,65 g/cm32410 °C4130 °C1803Tenant and andere
KPotassiumGermanKalium1939,0983 g/mol0,86 g/cm363,7 °C774 °C1807Davy
KrKrypton3683,8 g/mol3,48 g/l-156,6 °C-152,3 °C1898Ramsay and Travers
LaLanthanum57138,9055 g/mol6,16 g/cm3920 °C3454 °C1839Mosander
LiLithium36,941 g/mol0,53 g/cm3180,5 °C1317 °C1817Arfvedson
LrLawrencium103260,1053 g/mol1961Ghiorso
LuLutetium71174,967 g/mol9,84 g/cm31656 °C3315 °C1907Urbain
MdMendelevium101258,0986 g/mol1955Seaborg
MgMagnesium1224,305 g/mol1,74 g/cm3648,8 °C1107 °C1755Black
MnManganese2554,93805 g/mol7,44 g/cm31244 °C2097 °C1774Gahn
MoMolybdenum4295,94 g/mol10,28 g/cm32617 °C5560 °C1778Scheele
MtMeitnerium109266 g/mol1982Society for Heavy Ion Research
NNitrogen714,00674 g/mol1,17 g/l-209,9 °C-195,8 °C1772Rutherford
NaSodiumLatin Natrium1122,989768 g/mol0,97 g/cm397,8 °C892 °C1807Davy
NbNiobium4192,90638 g/mol8,58 g/cm32468 °C4927 °C1801Hatchet
NdNeodymium60144,24 g/mol7,00 g/cm31010 °C3127 °C1895von Welsbach
NeNeon1020,1797 g/mol0,84 g/l-248,7 °C-246,1 °C1898Ramsay and Travers
NiNickel2858,69 g/mol8,91 g/cm31453 °C2732 °C1751Cronstedt
NoNobelium102259,1009 g/mol1958Seaborg
NpNeptunium93237,0482 g/mol20,48 g/cm3640 °C3902 °C1940McMillan and Abelson
OOxygen815,9994 g/mol1,33 g/l-218,4 °C-182,9 °C1774Priestley and Scheele
OsOsmium76190,2 g/mol22,61 g/cm33045 °C5027 °C1803Tenant
PPhosphorus1530,973762 g/mol1,82 g/cm344 (P4) °C280 (P4) °C1669Brandt
PaProtactinium91231,0359 g/mol15,37 g/cm31554 °C4030 °C1917Soddy, Cranston and Hahn
PbLeadLatin Plumbum82207,2 g/mol11,34 g/cm3327,5 °C1740 °Cprehistoricunknown
PdPalladium46106,42 g/mol12,02 g/cm31552 °C3140 °C1803Wollaston
PmPromethium61146,9151 g/mol7,22 g/cm31080 °C2730 °C1945Marinsky and Glendenin
PoPolonium84208,9824 g/mol9,20 g/cm3254 °C962 °C1898Marie and Pierre Curie
PrPraseodymium59140,90765 g/mol6,48 g/cm3931 °C3212 °C1895von Welsbach
PtPlatinum78195,08 g/mol21,45 g/cm31772 °C3827 °C1557Scaliger
PuPlutonium94244,0642 g/mol19,74 g/cm3641 °C3327 °C1940Seaborg
RaRadium88226,0254 g/mol5,50 g/cm3700 °C1140 °C1898Marie and Pierre Curie
RbRubidium3785,4678 g/mol1,53 g/cm339 °C688 °C1861Bunsen and Kirchhoff
ReRhenium75186,207 g/mol21,03 g/cm33180 °C5627 °C1925Noddack, Tacke and Berg
RfRutherfordium104261,1087 g/mol1964/69Flerow oder Ghiorso
RgRoentgenium111272 g/mol1994Society for Heavy Ion Research
RhRhodium45102,9055 g/mol12,41 g/cm31966 °C3727 °C1803Wollaston
RnRadon86222,0176 g/mol9,23 g/l-71 °C-61,8 °C1900Dorn
RuRuthenium44101,07 g/mol12,45 g/cm32310 °C3900 °C1844Claus
SSulfur1632,066 g/mol2,06 g/cm3113 °C444,7 °Cprehistoricunknown
SbAntimonyLatin Stibium51121,75 g/mol6,69 g/cm3630,7 °C1750 °Cprehistoricunknown
ScScandium2144,95591 g/mol2,99 g/cm31539 °C2832 °C1879Nilson
SeSelenium3478,96 g/mol4,82 g/cm3217 °C685 °C1817Berzelius
SgSeaborgium106263,1182 g/mol1974Oganessian
SiSilicon1428,0855 g/mol2,33 g/cm31410 °C2355 °C1824Berzelius
SmSamarium62150,36 g/mol7,54 g/cm31072 °C1778 °C1879Lecoq de Boisbaudran
SnTinLatin Stannum50118,71 g/mol7,29 g/cm3232 °C2270 °Cprehistoricunknown
SrStrontium3887,62 g/mol2,63 g/cm3769 °C1384 °C1790Crawford
TaTantalum73180,9479 g/mol16,68 g/cm32996 °C5425 °C1802Ekeberg
TbTerbium65158,92534 g/mol8,25 g/cm31360 °C3041 °C1843Mosander
TcTechnetium4398,9063 g/mol11,49 g/cm32172 °C5030 °C1937Perrier and Segrè
TeTellurium52127,6 g/mol6,25 g/cm3449,6 °C990 °C1782von Reichenstein
ThThorium90232,0381 g/mol11,72 g/cm31750 °C4787 °C1829Berzelius
TiTitanium2247,88 g/mol4,51 g/cm31660 °C3260 °C1791Gregor and Klaproth
TlThallium81204,3833 g/mol11,85 g/cm3303,6 °C1457 °C1861Crookes
TmThulium69168,93421 g/mol9,32 g/cm31545 °C1727 °C1879Cleve
UUranium92238,0289 g/mol18,97 g/cm31132,4 °C3818 °C1789Klaproth
VVanadium2350,9415 g/mol6,09 g/cm31890 °C3380 °C1801del Rio
WTungstenGerman Wolfram74183,85 g/mol19,26 g/cm33407 °C5927 °C1783Gebrüder de Elhuyar
XeXenon54131,29 g/mol4,49 g/l-111,9 °C-107 °C1898Ramsay and Travers
YYttrium3988,90585 g/mol4,47 g/cm31523 °C3337 °C1794Gadolin
YbYtterbium70173,04 g/mol6,97 g/cm3824 °C1193 °C1878de Marignac
ZnZinc3065,39 g/mol7,14 g/cm3419,6 °C9 °Cprehistoricunknown
ZrZirconium4091,224 g/mol6,51 g/cm31852 °C4377 °C1789Klaproth
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