Formation of an Ionic Bond: Sodium Chloride Example

Introduction

• Demonstration by Lonnie on forming an ionic bond between sodium (Na) and chlorine (Cl) to create sodium chloride (NaCl).
• Sodium chloride is commonly known as table salt.

Materials Used

1. Elemental Chlorine (Cl₂)

   • Form: Chlorine gas
   • Appearance: Yellow gas

2. Solid Sodium Metal (Na)

   • Form: Shiny, silver, and soft metal
   • Characteristics:
     • Can be cut with a knife
     • Very reactive (reacts with air and water)
     • Stored under hexane to prevent reaction

Procedure

1. Preparation of Sodium:

   • Cut a small chunk of sodium and store it under hexane.
   • Clean the sodium surface and warm it slightly to initiate the reaction.
   • Use a spatula and flame to clean the surface and warm the sodium.

2. Reaction Process:

   • Sodium metal reacts with chlorine gas.
   • Energy Considerations:
     • Ionization energy of sodium > energy released when chlorine accepts electrons.
   • Ionic Bond Formation:
     • Positive ions (Na⁺) and negative ions (Cl⁻) form due to coulombic interaction.
     • Attraction between positive and negative ions releases energy.
   • Outcome:
     • Exothermic reaction visible by a bright red glow (typical of sodium emissions).
     • Formation of sodium chloride.

Conclusion

• Demonstrated the creation of sodium chloride, highlighting its characteristic as a common spice and food flavoring.
• Lonnie claims his lab-produced salt is superior to store-bought varieties, emphasizing the satisfaction of home production.

Important Points

• Reaction is driven by the coulombic attraction between oppositely charged ions.
• The exothermic nature of the reaction is a key indicator of energy release.
• The demonstration underscores both the chemical process and the qualitative benefits of producing sodium chloride.

Note: The demonstration serves as a practical example of ionic bonding, with real-life applications in producing a commonly used household substance.