The substances called chemically inert derive this characteristic from the fact that they are particularly stable. Naturally, the category of noble gases found on the periodic table is inert gases. Among these we find the following: helium, neon, argon, krypton, xenon and radon.
In addition to these basic elements, some chemical compounds are chemically inert. These compounds can be natural or synthetic. For example, silicon dioxide, also known as silica, is a compound that is generally chemically inert.
Chemically inert or not?
In order to put the inertness of certain compounds or elements into perspective, it is important to understand that an element/compound can be inert to one element/compound and reactive to another.
For example, carbon dioxide (CO2) is chemically inert to most chemical reactions. On the other hand, this same carbon dioxide can react violently with alkaline metals such as sodium or potassium.