In general, covalent compounds are poor conductors of electricity in both the solid and liquid states. This is because the electrons in covalent bonds are localized between the atoms and are not free to move and carry electric charge.

However, there are a few exceptions to this rule. For example, some covalent compounds, such as graphite, can conduct electricity in the solid state due to the presence of delocalized electrons. In graphite, the carbon atoms are arranged in a hexagonal lattice structure, and the electrons in the outer shells of the carbon atoms are free to move throughout the entire lattice. This allows graphite to conduct electricity in a similar manner to metals.

Additionally, some covalent compounds can conduct electricity in the liquid state if they are dissolved in a polar solvent. A polar solvent is a solvent that has a partial positive charge on one end of the molecule and a partial negative charge on the other end. When a covalent compound is dissolved in a polar solvent, the solvent molecules can interact with the covalent compound and cause the electrons to become delocalized. This can allow the compound to conduct electricity in solution.