The INTERNET Database of Periodic Tables
There are hundreds of periodic tables in web space, but there is only one comprehensive database of periodic tables & periodic system formulations. If you know of an interesting periodic table that is missing, please contact the database curator: Dr Mark R Leach.
Elemental Hydride Types Periodic Table
or Salt-Like Hydrides: Molten LiH conducts
electricity and hydrogen gas is liberated at the anode confirming presence
of hydride ion H. The crystal structures show an ionic
lattice, and not an LiH molecular lattice.
- Covalent Hydrides
are formed by the p-Bolock elements.
- Metallic or
Interstitial Hydrides are formed by many d-block and f-block elements
when heated with hydrogen under pressure. The hydrides tend to be non-stoichiometric
and they may be of variable composition.
- There is a Hydride
Gap where elements do not form hydrides. This roughly maps to the
Siderophile Elements of the geologist's periodic table (below).
- The Intermediate
Hydrides do not fit: beryllium hydride is polymeric, (BeH2)n.
Others have properties between metallic and covalent.
The main group elemental hydrides
are all well known reagent chemicals. The main group hydrides always give
the lowest and most common oxidation state, and all chemicals are molecular
in the gas phase. The Group I and II hydrides are ionic materials, but
they can be vaporised to give the molecular form.
The chemicals present and behave
as Lewis acids, Lewis bases or Lewis acid/base complexes, here:
Top of Page
|Periodic Table, What is it showing?
© Mark R. Leach 1999-
Queries, Suggestions, Bugs, Errors, Typos...
If you have any:
Suggestions or periodic table representations not shown on this page
Suggestions for links
Bug, typo or grammatical error reports about this page,
contact Mark R. Leach, the author, using firstname.lastname@example.org
This free, open
access web book is an ongoing project and your input is appreciated.