Here's why:

* Molecular Structure: CO2 molecules are nonpolar and have a linear structure. This means they do not have free electrons that can easily move and carry an electrical current.

* Bonding: The carbon and oxygen atoms in CO2 are held together by strong covalent bonds. These bonds are very stable and do not easily break to release free electrons.

* Insulating Properties: In fact, CO2 is often used as an insulating gas in some applications due to its poor electrical conductivity.

Exceptions:

* Plasma State: In its plasma state (at extremely high temperatures), CO2 can become conductive. This is because the intense heat breaks apart the molecules and creates free electrons and ions.

* Impurities: If CO2 contains impurities like water vapor or other conductive particles, its conductivity can increase slightly.

Overall, under normal conditions, CO2 is a very poor conductor of electricity.