Respuesta :
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.
The hard substance that has a high melting point and is a poor conductor of electricity in the solid phase could be NaCl.
Electrolytes
Electrolytes are substances which conduct electricity when in the molten or solution state.
Properties of Electrolytes.
- They are solids with high melting points
- They conduct electricity in the molten or solution state. Thus they were poor conductors in the solid state.
- They are usually acids, salts or bases.
- Examples are NaCl, KCl, HCl, KOH, etc.
Ionic compounds
Ionic compounds are compounds which are composed of oppositely charged ions held together by strong electrostatic forces. Ionic compounds all are electrolytes .
Properties of Ionic compounds
- They are solids with high melting points
- They are crystalline in nature
- They conduct electricity.
- Examples are NaCl, KCl, etc.
Therefore, the hard substance that has a high melting point and is a poor conductor of electricity in the solid phase could be NaCl.
Learn more about electrolytes and ionic substances at: https://brainly.com/question/4609389