Select the correct statement(s) for interstitial compounds.

Interstitial compounds formed when tiny atoms like H, C, and N become trapped inside the crystal lattice of transition metals.

Interstitial compounds have high melting point, higher than those of pure metals. Because the free element has the highest melting point of all the elements and is notable for its durability.

Higher than those of pure metals, they have high melting points. They are extremely tough; some interstitial compounds are nearly as hard as diamonds. They are chemically inert and preserve metallic conductivity.

All interstitial compounds retain metallic conductivity but are chemically inert.