Helium (He)

Atomic Number	2
Atomic Weight	4.002602
Massagetal	4

Group	18
Period	1
Block	s

proton	2 p⁺
neutron	2 n⁰
elektron	2 e^-

Physical Property

Atoomradius	120 pm 134 pm
molar volume	31,8 cm³/mol
Covalent Radius	46 pm 28 pm
Metallic Radius	122 pm
Ioonradius
Crystal Radius
Van der Waals radius	140 pm 140 pm 153 pm 236,2 pm
density	0,000164 g/cm³

Chemical Property

energie

proton affinity	177,8 kJ/mol
electron affinity	-19,7 eV/particle
ionization energy	24,587387936 eV/particle 54,41776311 eV/particle

Verdampingswarmte	0,08 kJ/mol
smeltingswarmte
Vormingsentalpie
elektron

Elektronskil	2

Valenselektrone	2 ⓘ

elektronkonfigurasie	1s²ⓘ

Oksidasietoestand
Elektronegatiwiteit	24,59 eV/particle 0.442712
Electrophilicity Index	0,0674191963846371 eV/particle
fundamental state of matter

phase of matter	Gas
gaseous state of matter	Monoatomic
Boiling Point	4,222 K
Melting Point
critical pressure	0,22746 MPa
critical temperature	5,195 K
triple point	2,177 K 5,043 kPa
appearance
kleur	Colorless #ffc0cb #d9ffff #d9ffff
appearance	colorless gas, exhibiting a red-orange glow when placed in a high-voltage electric field
Brekingsindeks	1,000035
thermodynamic material property
Thermal Conductivity	0,152 W/(m K)
thermal expansion
molar heat capacity	20,786 J/(mol K)
Specific Heat Capacity	5,193 J/(g⋅K)
heat capacity ratio	5/3
electrical properties
type
Geleidingsvermoë
Elektriese resistiwiteit
superconductivity
Magnetisme
type	diamagnetic
magnetic susceptibility (Mass)	-0,0000000059 m³/Kg
magnetic susceptibility (Molar)	-0,0000000000236 m³/mol
magnetic susceptibility (Volume)	-0,00000000105
magnetic ordering
Curie temperature
Néel temperature
structure
Crystal Structure	Face Centered Cubic (HEX)
lattice constant	3,57 Å
Lattice Angles	π/2, π/2, π/2
mechanical property
hardness
Massamodulus
Skuifmodulus
Young se modulus
Poisson se verhouding
Spoed van klank	970 m/s
classification
Category	Noble gases, Noble gases
CAS Group	VIII
IUPAC Group	VIIIA
Glawe Number	1
Mendeleev Number	112
Pettifor Number	1
Geochemical Class	volatile
Goldschmidt classification	atmophile

other

Gas Basicity	148,5 kJ/mol
polarizability	1,38375 ± 0,00002 a₀
C6 Dispersion Coefficient	1,42 a₀ 1,47 a₀
allotrope
Neutron cross section	0,007
Neutron Mass Absorption	0,00001
quantum number	1S0
Ruimtegroep	225 (Fm_3m)

Isotopes of Helium

Stable Isotopes	2
Unstable Isotopes	6
Natural Isotopes	2

³He

Massagetal	3
neutron number	1
Relative Atomic Mass	3,01602932197 ± 0,00000000006 Da
g-factor	-4,25525062 ± 0,00000006
natural abundance	0,0002 ± 0,0002
radioaktiwiteit	Stabiele isotoop
Halfleeftyd	Not Radioactive ☢️
spin	1/2
nuclear quadrupole moment	0
ontdekkingsdatum	1934
parity	+

⁴He

Massagetal	4
neutron number	2
Relative Atomic Mass	4,00260325413 ± 0,00000000016 Da
g-factor	0
natural abundance	99,9998 ± 0,0002
radioaktiwiteit	Stabiele isotoop
Halfleeftyd	Not Radioactive ☢️
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1908
parity	+

⁵He

Massagetal	5
neutron number	3
Relative Atomic Mass	5,012057224 ± 0,00002147 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	602 ± 22 ys
spin	3/2
nuclear quadrupole moment
ontdekkingsdatum	1937
parity	-

decay mode	intensity
n (neutron emission)	100%

⁶He

Massagetal	6
neutron number	4
Relative Atomic Mass	6,018885889 ± 0,000000057 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	806,92 ± 0,24 ms
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1936
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%
β⁻ d (β⁻-delayed deuteron emission)	0.000278%

⁷He

Massagetal	7
neutron number	5
Relative Atomic Mass	7,027990652 ± 0,000008115 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	2,51 ± 0,07 zs
spin	3/2
nuclear quadrupole moment
ontdekkingsdatum	1967
parity

decay mode	intensity
n (neutron emission)	100%

⁸He

Massagetal	8
neutron number	6
Relative Atomic Mass	8,033934388 ± 0,000000095 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	119,5 ± 1,5 ms
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1965
parity	+

decay mode	intensity
β⁻ (β⁻ decay)	100%
β⁻ n (β⁻-delayed neutron emission)	16%
β⁻ t (β⁻-delayed triton emission)	0.9%

⁹He

Massagetal	9
neutron number	7
Relative Atomic Mass	9,043946414 ± 0,000050259 Da
g-factor
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	2,5 ± 2,3 zs
spin	1/2
nuclear quadrupole moment	0
ontdekkingsdatum	1987
parity

decay mode	intensity
n (neutron emission)	100%

¹⁰He

Massagetal	10
neutron number	8
Relative Atomic Mass	10,052815306 ± 0,000099676 Da
g-factor	0
natural abundance
radioaktiwiteit	☢️ radioactive element
Halfleeftyd	260 ± 40 ys
spin	0
nuclear quadrupole moment	0
ontdekkingsdatum	1994
parity	+

decay mode	intensity
2n (2-neutron emission)	100%

geskiedenis

Ontdek deur	Sir William Ramsey, Nils Langet, P.T.Cleve
ligging van ontdekking	Scotland/Sweden
ontdekkingsdatum	1895
etimologie	Greek: hêlios (sun).
uitspraak	HEE-li-em (Engels)

source

Abundance
Abundance in Earth's crust	0,008 mg/kg
natural abundance (oseaan)	0,000007 mg/L
natural abundance (human body)
natural abundance (Meteoroïde)
natural abundance (Son)	23 %
Abundance in Universe	23 %

Nuclear Screening Constants

0.3125

Helium on ChemicalAid

ATC code	V03AN03
Australian Educational Vocabulary ID	scot/3528
BNCF	19752
BNF-kode	11978648w
Brockhaus Enzyklopädie online ID	helium-20
CAB ID	178029
CAS Registry Number	7440-59-7
ChEBI ID	30217
ChEMBL ID	CHEMBL1796997
ChemSpider ID	22423
Common Procurement Vocabulary	24111300
DSSTOX compound identifier	DTXCID5016402
DSSTox substance ID	DTXSID7036402
De Agostini ID	èlio
Den Store Danske ID	helium
DrugBank ID	09155
ECHA Substance Infocard ID	100.028.334
Encyclopædia Britannica Online ID	science/helium-chemical-element
Encyclopædia Universalis ID	helium
E number	E939
Freebase-kode	/m/025rt79
French Vikidia ID	Hélium
GND ID	4132459-6
Golden ID	Helium-K8NB
Great Russian Encyclopedia Online ID	2348591
HSDB ID	553
ICSC ID	0603
InChI	InChI=1S/He
InChIKey	SWQJXJOGLNCZEY-UHFFFAOYSA-N
Italian Vikidia ID	Elio
KBpedia ID	Helium
Klexikon article ID	Helium
Krugosvet article	nauka_i_tehnika/himiya/GELI.html
LCCN	sh85060043
MeSH descriptor ID	D006371
Mindat mineral ID	25563
NALT ID	44987
NDF-RT ID	N0000147379
NDL-kode	00563132
NE.se ID	helium
NKC-kode	ph503003
Namuwiki ID	헬륨
National Library of Israel J9U ID	987007555644805171
OmegaWiki Defined Meaning	7296
Online PWN Encyclopedia ID	3910758
OpenAlex ID	C546029482
OpenAlex ID	C2991909631
PSH ID	5816
Probes And Drugs ID	PD009020
PubChem CID	23987
Quora topic ID	Helium
RxNorm ID	5140
Römpp online ID	RD-08-00783
Spanish Vikidia ID	Helio
Store norske leksikon ID	helium
Treccani ID	elio
U.S. National Archives Identifier	10640583
UMLS CUI	C0018880
UNII	206GF3GB41
USGS Thesaurus ID	1470
WordNet 3.1 Synset ID	14664099-n
World of Physics ID	Helium
YSO ID	14499
ZVG number	7020

Helium (He)

Physical Property

Chemical Property

other

Isotopes of Helium

3He

4He

5He

6He

7He

8He

9He

10He

geskiedenis

source

Nuclear Screening Constants

³He

⁴He

⁵He

⁶He

⁷He

⁸He

⁹He

¹⁰He