Smith,+Morgan


 * Helium, He **



__Boiling Point:__ -268.93 degrees C __Melting Point:__ -272.2 degrees C  __Specific Gravity/Density:__ 0.1785 g/l __Number of protons:__ 2 __Number of neutrons:__ 2 __Number of electrons:__ 4 __Atomic mass:__ 4.01 __Atomic number:__ 2

[]

__Electron Configuration:__ 1s2 __ Orbital Notation: __ 1s2 __ Diagram of Bohr Model: __ [] __ Number of valence electons: __ 2 __How and When discovered?__ Jannssen obtained the first evidence of helium during the solar eclipse of 1868 when he found a new line in the solar spectrum. Lockyer and Frankland suggested the name helium for the new element. __Who discovered?__ Jules Cesar Janssen Where and how produced, processed, or mined?

__Chemical properties:__ unreactive, __Physical properties:__ colourless Minerals, compounds, or ores in which found:

__Two common chemical reactions:__ 1.) filling up balloons 2.) cooling medium for nuclear reactors __ Industrial or commercial uses: __ uses in balloons and laughing gas commercial; uses in Bulk Liquid Helium and Speciality Gas and Ultra High Purity Helium [] __Cost or value:__ the cost of helium depends on the grade you are looking for, the helium used to inflate balloons is about $20 for about 9 cubic feet at most large department store chains. __ Unusual Facts: __
 * noble gases
 * Speaking after breathing an atmosphere rich in helium results in a squeaky voice
 * Most abundant element in the universe
 * Natural gas

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