Ask A Scientist© Chemistry Archive

name        Snezana
status      student
age         20s

Question -  The noble metals are Cu, Ag, Au, Pt, Pd, sometimes Ir.
What about Ru and Ti? Aren't they noble metals as well?
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Historically, the noble metals I suppose were "noble" because you had to be
a rich noble to afford to own any. It then took on the connotation of
non-reactive because Cu, Ag, Au, Pt, and Pd are frequently found as metallic
ores, rather than as oxides, sulfides or other compounds.

This whole concept has lost its meaning of "non-reactive" as modern
chemistry and metallurgy have discovered other elements such as Ru, Ti, Ta,
and others that are quite resistant to heat and chemical attack.

Vince Calder
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Hi Snezana!
To call metals "noble" is a classification somehow out-of-date... it means
that
in the activity series of metals they are placed after the hydrogen and
then, do not
react with acids to form hydrogen. These metals are in order: copper,
silver,
mercury, platinum and gold.  Noble also could mean they are beautiful,
  precious, and valuable and are used to make jewlery,  mostly silver, gold
and
platinum. And also can mean they are very difficult to be attacted or to
react
chemically...like the  other metals from the  platinum group.
OK? and thanks for asking NEWTON!
Mabel
(Dr. Mabel Rodrigues)
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