Which of the following does not apply to metallic bond?

The boiling points of noble gases are illustrative of the operation of forces of the type:

The compound,found in nature in gas phase but ionic in solid state is

What type of bonds are present in molecular crystals?

Which of the following is not applicable to metallic bonding?

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 $NaCl_{(s)}$.