Hydrogen
Hydrogen is quite possibly my second favorite element. This is because hydrogen (protium) has
a unique quality--it doesn't have a neutron. (However, deuterium and tritium,
isotopes of hydrogen, have 1 and 2 neutrons respectively.) Hydrogen, the
first element on the periodic table, is a gas, and has an atomic mass of
1.00794 amu. It was discovered in 1766 by Henry Cavendish of England.
Hydrogen is also special because it is the most common element in the universe.
"Hydrogen" is Greek for "forming water," as hydrogen makes up 11% of water.
All heavier elements are built from hydrogen, as well as helium.
It is debated whether hydrogen is a metal or a nonmetal, and has been placed both
above lithium and next to helium in the periodic table, while sometimes it is off on its
own. Hydrogen melts at -259.34 degrees celcius, and freezes at
-252.87 degrees celcius.
Hydrogen's electron configuration is 1s1.
H's electronegativity is 2.10.
The density of H at STP (20 degrees C, 1 atm) is 0.0899 g/L.
May 18, 1997, updated August 7, 1998
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