Give two properties in which interstitial compounds differ from its elements.

Explanation

To answer the question regarding the properties in which interstitial compounds differ from their parent elements, we can follow these steps:

### Step 1: Define Interstitial Compounds
Interstitial compounds are formed when small atoms such as hydrogen, carbon, or nitrogen occupy the interstitial spaces (the gaps) in the crystal lattice of transition metals. This definition is crucial as it sets the context for understanding the properties of these compounds.

### Step 2: Identify the First Property - Melting Point
One notable property of interstitial compounds is that they have very high melting points. In fact, the melting points of these compounds are often higher than those of the parent transition metals from which they are derived. This is due to the strong bonding interactions between the small atoms and the metal lattice.

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