Combustion Reaction: Ethane (C2H6)

Overview

• Discussing a combustion reaction involving ethane (C2H6).
• Reaction with molecular oxygen (O2) to form carbon dioxide (CO2) and water (H2O).
• Emphasis on balancing the chemical equation.

Balancing the Equation

• Initial Observation:

  • Ethane: 2 carbons, 6 hydrogens (C2H6)
  • Combusts with O2 gas.
  • Produces CO2 and H2O.

• Balancing Steps:

  • Carbons:
    • Left: 2 carbons.
    • Right: 1 carbon.
    • Adjust: Use 2 CO2 on the right to balance carbons.
  • Hydrogens:
    • Left: 6 hydrogens.
    • Right: 2 hydrogens.
    • Adjust: Use 3 H2O on the right to balance hydrogens.
  • Oxygens:
    • Left: 2 oxygens.
    • Right: 4 (from CO2) + 3 (from H2O) = 7 oxygens.
    • Adjust: Use 3.5 O2 on the left to balance oxygens.

Achieving Whole Number Coefficients

• Multiplying all coefficients by 2 to avoid fractional coefficients:
  • Ethane: 1 becomes 2.
  • O2: 3.5 becomes 7.
  • CO2: 2 becomes 4.
  • H2O: 3 becomes 6.
• New Balanced Equation:
  • 2 C2H6 + 7 O2 → 4 CO2 + 6 H2O
  • Ensures all coefficients are whole numbers.

Conclusion

• Successfully balanced the combustion reaction of ethane by adjusting coefficients.
• Highlighted strategy of saving dioxygen (O2) for last due to its standalone nature for easier adjustments.