Helium: Difference between revisions

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'''Helium''' is a [[Chemical elements|chemical element]], having the [[chemical symbol]] He. Its [[atomic number]] (the number of [[proton]]s) is 2. It has a [[Atomic mass#Standard atomic weights of the elements|standard atomic weight]] of 4.002602 g•mol<sup> −1</sup>, and is typically found as a [[gas]] in its elemental form.
'''Helium''' is a [[Chemical elements|chemical element]], having the [[chemical symbol]] He. Its [[atomic number]] (the number of [[proton]]s) is 2. It has a [[Atomic mass#Standard atomic weights of the elements|standard atomic weight]] of 4.002602 g•mol<sup> −1</sup>, and is typically found as a [[gas]] in its elemental form.


Helium is considered to be a member of the "Noble gas" class of element. At a [[pressure]] of 101.325 k[[Pascal (unit)|Pa]], it has a [[boiling point]] of -268.93 °[[Celsius (unit)|C]], and a [[melting point]] of -272.2 °C.
Helium is a monatomic noble gas. At a [[pressure]] of 101.325 k[[Pascal (unit)|Pa]], it has a [[boiling point]] of -268.93 °[[Celsius (unit)|C]], and a [[melting point]] of -272.2 °C.

Revision as of 15:08, 8 March 2016

This article is a stub and thus not approved.
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Helium
4.002602(2)



  He
2
1s2
[ ? ] Noble gas:
Properties:
Inert, colorless, odorless, non-toxic, non-flammable gas
Uses:
Cryogenics, welding, inert purging gas, scientific uses

Helium is a chemical element, having the chemical symbol He. Its atomic number (the number of protons) is 2. It has a standard atomic weight of 4.002602 g•mol −1, and is typically found as a gas in its elemental form.

Helium is a monatomic noble gas. At a pressure of 101.325 kPa, it has a boiling point of -268.93 °C, and a melting point of -272.2 °C.