Inertness is evaluated through various methods: 1. Chemical Stability: This involves testing the catalyst in different chemical environments to ensure it does not react. 2. Thermal Stability: The catalyst is subjected to high temperatures to check if it remains unchanged. 3. Spectroscopic Analysis: Techniques like X-ray diffraction and NMR spectroscopy can be used to analyze the structure of the catalyst before and after the reaction to ensure it remains intact.