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Question
Mention the type of compounds formed when small atoms like H, C and N get trapped inside the crystal lattice of transition metals. Also give physical and chemical characteristics of these compounds.
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Solution
Compounds formed when small atoms like H, C and N get trapped inside the crystal lattice of transition metals are called interstitial compounds.
Properties of such compounds are:
(i) High melting points higher than those of pure metals.
(ii) These compounds are very hard.
(iii) They retain metallic conductivity.
(iv) They are chemically inert.
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