Which of the following does not conduct electricity?

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 $NaCl_{(s)}$.

Which solid will have the weakest intermolecular forces?

Identify the type of intermolecular force present between benzene $(C_6H_6)$ and ammonia $(NH_3)$.

Graphite is a soft solid lubricant and is extremely difficult to melt. What is the reason for this behavior of graphite?

Which of the following processes is exothermic?