Question

formation of interstitation compound makes the transtition metal

Answer 1

Answer: Hard
Most transition metals form interstitial compounds with small non metal atoms such as H, Bo, C and N.
These small atoms enter the voids between packed atoms of crystalline transition metals.
They form chemical bonds with them, for example, steel and iron becomes harder by forming interstitial compounds with Carbon.

Answer 2

Formation of interstitial compound makes the transition metal hard.
Transition metals are large in size and contain lots of interstitial sites. Transition elements can trap atoms of other elements (that have the small atomic size), such as H, C, N, in the interstitial sites of their crystal lattices. The resulting compounds are called the interstitial compound.

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