Introduction

• Ionic Compounds: Formed by the transfer of electrons between metals and non-metals, resulting in ions held together by strong electrostatic forces.

• Example: Sodium chloride (NaCl).

• Covalent Compounds: Formed by the sharing of electrons between two non-metals.
  • Example: Water (H₂O).

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Properties of Ionic Compounds

• Physical State:
  • Usually solid at room temperature.
  • Have a crystalline structure.

• Melting and Boiling Points:
  • High melting and boiling points due to strong electrostatic forces of attraction between ions.
• Solubility:
  • Soluble in polar solvents like water.
  • Insoluble in non-polar solvents like benzene.

• Electrical Conductivity:

• Conduct electricity in molten or aqueous state due to free-moving ions.
• Do not conduct electricity in solid state as ions are fixed in the lattice.
• Strength of Bonds:
  • Ionic bonds are strong, resulting in a rigid and brittle structure.
• Examples:
  • NaCl, MgO, CaCl₂.

Comparison of Ionic and Covalent Compounds

Property	Ionic Compounds	Covalent Compounds
Formation	Transfer of electrons	Sharing of electrons
Bond Type	Ionic bond (electrostatic force)	Covalent bond
Melting/Boiling Points	High	Low
Solubility	Soluble in water, insoluble in non-polar solvents	Soluble in non-polar solvents, insoluble in water
Electrical Conductivity	Conduct in molten/aqueous state	Non-conductors
Physical State	Solid	Solid, liquid, or gas

Key Differences

1. Nature of Bonding:
   • Ionic compounds form strong electrostatic bonds.
   • Covalent compounds form shared electron pairs.
2. Behavior in Water:
   • Ionic compounds dissociate into ions.
   • Covalent compounds do not dissociate easily.
3. Hardness:
   • Ionic compounds are hard but brittle.
   • Covalent compounds are softer.

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Examples in Daily Life

• Ionic Compounds:
  • Common salt (NaCl) used in cooking.
  • Baking soda (NaHCO₃) used in baking.

• Covalent Compounds:
  • Sugar (C₆H1₁₂O₆) in food.
  • Water (H₂O) essential for life.

Conclusion

Understanding the properties of ionic and covalent compounds helps explain their different uses and behaviors in real-life applications. The type of bonding significantly influences a compound’s physical and chemical properties.