Which of the following statements is true about the formation of interstitial compounds?
Interstitial compounds are formed when large atoms occupy the interstitial sites of the crystal lattice
The crystal lattice of the parent metal is not distorted in the formation of interstitial compounds
Interstitial compounds have lower melting and boiling points than their parent metals
Interstitial compounds are always harder and more brittle than their parent metals
Interstitial compounds are formed when small atoms, such as hydrogen, carbon, and nitrogen, occupy the interstitial sites of the crystal lattice of the transition metal. Due to the small size of these atoms, they can easily fit into the interstitial sites, resulting in a distortion of the crystal lattice. As a result, interstitial compounds are usually harder and more brittle than their parent metals. They also have higher melting and boiling points than their parent metals because of the strong metallic bonding between the metal atoms and the small atoms occupying the interstitial sites.