Which of the following does not apply to metallic bond?

The solid phosphorus pentachloride exists as:

Which among the following forces of attraction is developed between polar and non-polar molecules?

From the following,which compound on heating readily sublimes?

The lattice enthalpy of an ionic compound is the enthalpy change when one mole of an ionic compound in its solid state dissociates into its ions in the gaseous state. It is impossible to determine it directly by experiment. Suggest and explain an indirect method to measure the lattice enthalpy of $NaCl_{(s)}$.

Solid $PCl_5$ exists as $:$