Question
Write the properties of covalent compounds, and how these properties differ from that of NaCl.
Answer
The properties of covalent compounds are:
- Low melting and boiling points: Covalent compounds have weak intermolecular forces between molecules, so they have lower melting and boiling points than ionic compounds.
- Insolubility in water: Covalent compounds are generally insoluble in water as they do not dissociate into ions and therefore cannot form hydrogen bonds with water molecules.
- Non-conductivity: Covalent compounds do not conduct electricity in any state because they do not have free-charged particles.
- Softness: Covalent compounds are generally soft and have a low hardness because their molecules are held together by weak intermolecular forces.
Comparison with NaCl (Ionic Compound):
- NaCl (ionic) has high melting and boiling points, while covalent compounds have lower melting and boiling points.
- NaCl is highly soluble in water, whereas many covalent compounds are either poorly soluble or insoluble.
- NaCl conducts electricity when dissolved in water or molten, but covalent compounds do not conduct electricity in either state.
- NaCl is a solid at room temperature, while covalent compounds can exist as solids, liquids, or gases at room temperature.
