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Question
Why are interstitial compounds well known for transition metals?
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Solution
Interstitial compounds do not correspond to any normal oxidation state of the metal. Because of their composition, these compounds are referred to as interstitial compounds. The principal physical and chemical characteristics of these compounds are as follows:
- They have high melting points, higher than those of pure metals.
- They are very hard; some borides approach diamond in hardness.
- They retain metallic conductivity.
- They are chemically inert.
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