Geliy
2
He
Guruh
18
Davr
1
Block
s
Protonlar
Elektronlar
Neytronlar
2
2
2
General Properties
Atom raqami
2
Atom massasi
4,002602
Mass Number
4
Turkum
Inert gazlar
Ranggi
Rangsiz
Radioaktivlik
Yoʻq
From the Greek word helios, the sun
Crystal Structure
Face Centered Cubic
Tarix
French astronomer Jules Janssen obtained the first evidence of helium during the solar eclipse of 1868.
Norman Lockyer and Edward Frankland suggested the name helium for the new element.
In 1895, Sir William Ramsay discovered helium in the uranium mineral cleveite.
It was independently discovered in cleveite by Per Teodor Cleve and Abraham Langlet.
Norman Lockyer and Edward Frankland suggested the name helium for the new element.
In 1895, Sir William Ramsay discovered helium in the uranium mineral cleveite.
It was independently discovered in cleveite by Per Teodor Cleve and Abraham Langlet.
Electrons per shell
2
Elektron konfiguratsiyasi
1s2
Unlike any other element, helium will remain liquid down to absolute zero at normal pressures
Physical Properties
Phase
Gas
Zichlik
0,0001785 g/cm3
Erish harorati
0,95 K | -272,2 °C | -457,96 °F
Qaynash harorati
4,22 K | -268,93 °C | -452,07 °F
Heat of Fusion
0,02 kJ/mol
Heat of Vaporization
0,083 kJ/mol
Solishtirma issiqlik sigʻimi
5,193 J/g·K
Abundance in Earth's crust
5,5×10-7%
Abundance in Universe
23%
CAS Number
7440-59-7
PubChem CID Number
23987
Atomic Properties
Atom radiusi
31 pm
Kovalentlik radiusi
28 pm
Elektrmanfiylik
-
Ionization Potential
24,5874 eV
Molyar hajm
27,2 cm3/mol
Issiqlik oʻtkazuvchanlik
0,00152 W/cm·K
Oksidlanish darajasi
0
Applications
Helium is used as a protective gas in growing silicon and germanium crystals, in titanium and zirconium production, and in gas chromatography.
Helium at low temperatures is used in cryogenics.
Helium is used for filling balloons and for pressurizing liquid fuel rockets.
Helium is used as a shielding gas in arc welding processes.
Helium at low temperatures is used in cryogenics.
Helium is used for filling balloons and for pressurizing liquid fuel rockets.
Helium is used as a shielding gas in arc welding processes.
Helium is not known to be toxic
Izotoplar
Barqaror izotoplar
3He, 4HeBeqaror izotoplar
5He, 6He, 7He, 8He, 9He, 10He