Question

An unknown compound does not dissolve in water, is a nonelectrolyte and has a low melting point. Would it be an ionic compound? Explain.

Answer 1

No, it's not an ionic compound.
The distinguishing properties of ionic compounds are that they dissolve in water (water's polarity pulls the ions apart), are electrolytes (dissociate into ions, which conduct electricity), and have high melting points (it takes a lot of energy to separate the ions without water or other polar compounds). Since the unknown compound has the opposite of all these properties, it's not ionic.