Introduction:
Naphthalene and benzene are both hydrocarbon compounds, but naphthalene is more reactive than benzene. In this response, we will explain in detail why naphthalene is more reactive than benzene.

Structure:
The structure of naphthalene is different from that of benzene. Naphthalene is a bicyclic compound, which means it contains two rings fused together. The two rings in naphthalene are connected by a shared bond, which creates a structure that is less stable than benzene.

Electron Density:
Naphthalene has a higher electron density than benzene because of the additional ring. The two rings in naphthalene can interact with each other, causing a redistribution of electrons. This interaction creates regions of higher electron density, making naphthalene more reactive than benzene.

Reactivity:
The higher electron density in naphthalene makes it more reactive than benzene. Naphthalene can undergo reactions such as addition, substitution, and oxidation more readily than benzene. Additionally, naphthalene can undergo reactions that benzene cannot, such as Diels-Alder cycloaddition reactions.

Conclusion:
In conclusion, naphthalene is more reactive than benzene due to its unique structure and higher electron density. Naphthalene can undergo a wider range of reactions than benzene, making it a more versatile compound in organic chemistry.