Helium | SSHADE

Atom

Name: Helium

Name and identifiers

IUPAC name: Helium
InChI: InChI=1S/He
InChI key: SWQJXJOGLNCZEY-UHFFFAOYSA-N
CAS number: 7440-59-7
Comments: natural He, 99.9999% 4He

Symbol and fundamental properties

Symbol: He
Formula: $He$
Charge: 0
Atomic number Z: 2

Molar mass: 4.002602 $g/mol$
State STP: gas
Electronegativity: 0.0

Isotopic composition

Isotope mixture type

terrestrial abundance

Isotopes

	IUPAC Name	A	Mole fraction
	Helium-3	3	1.34e-06
	Helium-4	4	0.99999866

X-ray absorption edges

Type	K
Energy (keV)	0.0246