Question

A hard substance that has a high melting point and is a poor conductor of electricity in the solid phase could be

Answer 1

Answer:

C) NaCl

Explanation:

A hard substance that has a high melting point and is a poor conductor of electricity in the solid phase could be NaCl

This because it is an ionic compound.

• Ionic compounds are formed via the electrostatic attraction between oppositely charged ions.
• Ionic substances have high melting point as solids and as liquids, they have a high boiling point.
• In aqueous solutions or in molten form, ionic compounds can conduct an electric current using free mobile ions as carriers.
• In solid state, the ions are arranged into a crystal lattice and will not conduct a current of electricity.

Compounds like NaCl, MgO, NaF are in this category.