Helij

Helij (He)

kemijski element simbola He, lagani plemeniti plin, korišten za punjenje balona
Atomski broj2
Relativna atomska masa4.002602
Maseni broj4
Skupina18
Perioda1
Bloks
proton2 p+
neutron2 n0
elektron2 e-
Animated Bohrov model atoma of He (Helij)

Physical Property

Atomski Radijus
120 pm
Molni volumen
Kovalentni Radijus
46 pm
Metallic Radius
Ionski radijus
Crystal Radius
Van der Waals radius
140 pm
gustoća
0,000164 g/cm³
Atomic Radii Of The Elements: Helij0102030405060708090100110120130140pmAtomski RadijusKovalentni RadijusMetallic RadiusVan der Waals radius

Kemijsko Svojstvo

energija
proton affinity
177,8 kJ/mol
Elektronski afinitet
−19,7 eV/particle
ionization energy
24,587387936 eV/particle
ionization energy of He (Helij)
Toplina isparivanja
0,08 kJ/mol
toplina taljenja
standard enthalpy of formation
elektron
Elektronska ljuska2
Bohrov model atoma: He (Helij)
valence electron2
Lewis structure: He (Helij)
electron configuration1s2
Enhanced Bohrov model atoma of He (Helij)
Orbital Diagram of He (Helij)
Oksidacijski broj
Elektronegativnost
Electrophilicity Index
0,0674191963846371 eV/particle
fundamental state of matter
agregatno stanjePlinovito
gaseous state of matterMonoatomic
Vrelište
4,222 K
Talište
critical pressure
0,22746 MPa
critical temperature
5,195 K
Trojna točka
2,177 K
5,043 kPa
appearance
boja
Bezbojan
appearancecolorless gas, exhibiting a red-orange glow when placed in a high-voltage electric field
Indeks prelamanja
1,000035
thermodynamic material property
Toplinska vodljivost
0,152 W/(m K)
Toplinsko istezanje
molar heat capacity
20,786 J/(mol K)
Specifični toplinski kapacitet
5,193 J/(g⋅K)
heat capacity ratio5/3
electrical properties
type
electrical conductivity
Električna otpornost i provodnost
Supravodljivost
Magnetizam
typediamagnetic
Magnetna susceptibilnost (Mass)
−0,0000000059 m³/Kg
Magnetna susceptibilnost (Molar)
−0,0000000000236 m³/mol
Magnetna susceptibilnost (Volume)
−0,00000000105
magnetic ordering
Curieva temperatura
Néel temperature
struktura
Kristalna strukturaKubna plošno centrirana (HEX)
lattice constant
3,57 Å
Lattice Anglesπ/2, π/2, π/2
mechanical property
Tvrdoća
bulk modulus
shear modulus
Youngov modul elastičnosti
Poissonov omjer
brzina zvuka
970 m/s
classification
KategorijaPlemeniti plinovi, Noble gases
CAS GroupVIII
IUPAC GroupVIIIA
Glawe Number1
Mendeleev Number112
Pettifor Number1
Geochemical Classvolatile
Goldschmidt classificationatmophile

other

Gas Basicity
148,5 kJ/mol
polarizability
1,38375 ± 0,00002 a₀
C6 Dispersion Coefficient
1,42 a₀
allotrope
Nuklearni udarni presjek
0,007
Neutron Mass Absorption
0,00001
Kvantni brojevi1S0
space group225 (Fm_3m)

Isotopes of Helium

Stabilni izotopi2
Nestabilni izotopi6
Natural Isotopes2
Isotopic Composition4100.00%4100.00%30.00%30.00%

3He

Maseni broj3
neutron number1
Relativna atomska masa
3,01602932197 ± 0,00000000006 Da
g-factor
−4,25525062 ± 0,00000006
natural abundance
0,0002 ± 0,0002
radioaktivnoststable isotope
Vrijeme poluraspadaNot Radioactive ☢️
spin1/2
nuclear quadrupole moment
0
vrijeme otkrića ili izuma1934
Parnost+

4He

Maseni broj4
neutron number2
Relativna atomska masa
4,00260325413 ± 0,00000000016 Da
g-factor
0
natural abundance
99,9998 ± 0,0002
radioaktivnoststable isotope
Vrijeme poluraspadaNot Radioactive ☢️
spin0
nuclear quadrupole moment
0
vrijeme otkrića ili izuma1908
Parnost+

5He

Maseni broj5
neutron number3
Relativna atomska masa
5,012057224 ± 0,00002147 Da
g-factor
natural abundance
radioaktivnost☢️ radioactive element
Vrijeme poluraspada
602 ± 22 ys
spin3/2
nuclear quadrupole moment
vrijeme otkrića ili izuma1937
Parnost-

decay modeintensity
n (neutron emission)100%

6He

Maseni broj6
neutron number4
Relativna atomska masa
6,018885889 ± 0,000000057 Da
g-factor
0
natural abundance
radioaktivnost☢️ radioactive element
Vrijeme poluraspada
806,92 ± 0,24 ms
spin0
nuclear quadrupole moment
0
vrijeme otkrića ili izuma1936
Parnost+

decay modeintensity
β (β decay)100%
β d (β-delayed deuteron emission)0.000278%

7He

Maseni broj7
neutron number5
Relativna atomska masa
7,027990652 ± 0,000008115 Da
g-factor
natural abundance
radioaktivnost☢️ radioactive element
Vrijeme poluraspada
2,51 ± 0,07 zs
spin3/2
nuclear quadrupole moment
vrijeme otkrića ili izuma1967
Parnost

decay modeintensity
n (neutron emission)100%

8He

Maseni broj8
neutron number6
Relativna atomska masa
8,033934388 ± 0,000000095 Da
g-factor
0
natural abundance
radioaktivnost☢️ radioactive element
Vrijeme poluraspada
119,5 ± 1,5 ms
spin0
nuclear quadrupole moment
0
vrijeme otkrića ili izuma1965
Parnost+

decay modeintensity
β (β decay)100%
β n (β-delayed neutron emission)16%
β t (β-delayed triton emission)0.9%

9He

Maseni broj9
neutron number7
Relativna atomska masa
9,043946414 ± 0,000050259 Da
g-factor
natural abundance
radioaktivnost☢️ radioactive element
Vrijeme poluraspada
2,5 ± 2,3 zs
spin1/2
nuclear quadrupole moment
0
vrijeme otkrića ili izuma1987
Parnost

decay modeintensity
n (neutron emission)100%

10He

Maseni broj10
neutron number8
Relativna atomska masa
10,052815306 ± 0,000099676 Da
g-factor
0
natural abundance
radioaktivnost☢️ radioactive element
Vrijeme poluraspada
260 ± 40 ys
spin0
nuclear quadrupole moment
0
vrijeme otkrića ili izuma1994
Parnost+

decay modeintensity
2n (2-neutron emission)100%
Helium discharge tube

povijest

otkrio/izumioSir William Ramsey, Nils Langet, P.T.Cleve
location of discoveryScotland/Sweden
vrijeme otkrića ili izuma1895
EtimologijaGreek: hêlios (sun).
pronunciationHEE-li-em (engleski)

source

Obilnost
Zastupljenost u Zemljinoj kori
0,008 mg/kg
natural abundance (ocean)
0,000007 mg/L
natural abundance (tijelo)
natural abundance (meteoroid)
natural abundance (Sunce)
23 %
Zastupljenost u svemiru
23 %

Nuclear Screening Constants

1s0.3125