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Wikipedia:Today's featured article/May 31, 2004

From Wikipedia, the free encyclopedia
Helium on the periodic table
Helium on the periodic table

Helium is the chemical element in the periodic table that has the symbol He and atomic number 2. A colorless, odorless noble gas, helium has the lowest boiling point of any element and can only be solidified under great pressure. This element occurs as a monatomic gas. It is for practical purposes chemically inert. It is the second most abundant element in the universe after hydrogen. It is found in the Earth's atmosphere in trace amounts from the decay of certain minerals and is present in some mineral waters. Helium occurs in economically extractable amounts in certain natural gases and is used as a lifting gas for balloons and blimps, as a cryogenic cooling liquid for superconducting magnets. (more...)

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