Why are metals good conductors of electricity?

Metals are good conductors of electricity primarily because they have loosely held electrons that can move freely. In metallic bonding, atoms share a "sea of electrons" which are not bound to any specific atom but are free to move throughout the metallic structure. This mobility of electrons allows them to carry electrical charge effectively when a potential difference is applied, resulting in the conduction of electricity.

In this context, tightly packed atoms, the formation of ionic compounds, and high melting and boiling points do not directly explain the ability of metals to conduct electricity. While tightly packed atoms contribute to the overall structure and stability of metals, it is the free movement of the electrons that is critical for electrical conductivity. Ionic compounds, on the other hand, require a liquid state or solution to conduct electricity, as solid ionic compounds do not allow free movement of ions. Finally, while metals often do have high melting and boiling points, this characteristic is not related to their electrical conductivity but rather due to the strength of the metallic bonds.