Helium

From Lunarpedia
Revision as of 13:37, 13 February 2007 by Jarogers2001 (talk | contribs) (Restored lost content)
Jump to: navigation, search
Helium
He
In situ availability: trace
Necessity:
Atomic number: 2
Atomic mass: 4.002602
group: 18
period: 1
normal phase: Gas
series: Noble gases
density: 0.1786 g/L
melting point: 0.95K,
-272.2°C,
-458.0°F
boiling point: 4.22K,
-268.93°C,
-452.07°F
N/AN/AN/A
H ← He → Li
FNeN/A
Atomic radius (pm): 31 pm
Bohr radius (pm):
Covalent radius (pm): 32
Van der Waals radius (pm): 140
ionic radius (pm): -
1st ion potential (eV): 24.59
Electron Configuration
1s2
Electrons Per Shell
2
Electronegativity:
Electron Affinity: Unstable anion
Oxidation states: -
Magnetism:
Crystal structure: Hexagonal or body centered cubic

Helium is a Noble gas in group 18. It has a Hexagonal or body centered cubic crystalline structure. This element has two stable isotopes: 3 and 4.

Helium is the second element in the periodic table. It is a noble gas.

Helium consists of two isotopes. The most common isotope, Helium-4, has a nucleus of two protons and two neutrons, and two electrons. The less common isotope Helium-3 has two protons and one neutron.

Helium is a component of the solar wind, and hence is found (in parts per million level) in Lunar regolith.



This article is an automatically generated stub. As such it may contain serious errors.
You can help Lunarpedia by expanding or correcting it.