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What are interstitial compounds?

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What are interstitial compounds?

What are interstitial compounds? Why do these compounds have higher melting points than corresponding pure metals?

Short Answer
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Solution

  1. Interstitial compounds are those which are formed when small atoms like H, C, N, B, etc. are trapped inside the crystal lattice of metals.
  2. They have a higher melting point than metals because the metal-nonmetal bonds are stronger than the metal-metal bonds in pure metals.
  3. They are usually non-stoichiometric and are neither typically ionic nor covalent; for example, TiC, Mn4N, Fe3H, VH0.56, and TiH1.7.
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Chapter 4: The d-block and f-block Elements - Exercises [Page 115]

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NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 4 The d-block and f-block Elements
Exercises | Q 4.12 (i) | Page 115

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