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Group I actually contains also the alkali
metals but hydrogen (H) is not counted among them and thus rates a separate page.
Hydrogen accounts for much of
the universe - about 93 %. Helium (He) provides a bit less than 7 %; the rest thus
can be seen as trace elements; the ash of burnt-out stars. |
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Jupiter and Saturn, the big planets of our solar system, consist mostly of hydrogen
while or earth contains only about 0.12 % (more or less in the water of the oceans). That still makes hydrogen, after oxygen
(O) and silicon (Si), the third most frequent element. The earth is too small to hold gaseous hydrogen for long, and so
are the other smaller planets. |
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In the human body hydrogen accounts for about 60 % of the elements, so nothing needs to be
said about its importance in organic chemistry. World production of hydrogen is around 150 Mio tons a year. If we ever switch
from an oil / coil driven economy to a hydrogen-fueled one, this number will have to go up tremendously. |
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Table of Basic Data |
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Name
(German) |
Hydrogen
Wasserstoff |
| Atomic number | 1 |
| Atomic mass [u] |
1
2 = Deuterium, 3 = Tritium |
| Melting point [K] | 14 |
| Melting point [oC] |
–259 |
| Melting point [oF] |
-434 | | Boiling point [K]
| 20 |
| Density [g/cm3] gas |
8,4 ·10–5
(Record low) |
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In case of doubt all numbers are for room temperatures |
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fcc = face centered
cubic; lattice const. = a
bcc = body centered
cubic
sc = simple cubic
hp = simple hexagonal
hcp = hexagonal close packed; lattice constants a and
c.
op = simple orthorhombic, monoclinic, triclinic
tp = simple tetragonal
dia = diamond structure
r = trigonal or rhomboedral trigonal |
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© H. Föll (Iron, Steel and Swords script)
With frame
Glossary