There isn't a single chemical symbol for an inert element. "Inert" usually refers to the noble gases, which are a group of elements on the periodic table known for their lack of reactivity. Here are the symbols for the noble gases:

* He - Helium

* Ne - Neon

* Ar - Argon

* Kr - Krypton

* Xe - Xenon

* Rn - Radon

While these elements are often called "inert," they can actually react under certain extreme conditions.