Question

Balance the equation for the complete combustion of ethane: C₂H₆ (g) + O₂ (g) ⟶⟶CO₂ (g) + H₂O (g). Calculate ΔΔH^ofor the reaction per mole of ethane using the given bond dissociation energies.

→CO2(g) + H2O (g). Calculate AH° for Balance the equation for the complete combustion of ethane: C2H6 (g) + O2(g) the reaction per mole of ethane using the given bond dissociation energies. Bond AH” (kJ/mol) C-C 347 H-O 467 C-H 413 O=0 498 C=0 799 CO 358

Answer 1

The balanced reaction is:

2 C2H6(g) + 7 O2(g) —> 4 CO2(g) + 6 H2O(g)

On reactant we have:

12 C-H bond

2 C-C bond

7 O=O bond

On product we have:

8 C=O bond

12 O-H bond

So,

Delta H = BE(reactant) - BE(product)

= 12*BE(C-H) + 2*BE(C-C) + 7*BE(O=O) - 8*BE(C=O) - 12*BE(O-H)

= 12 * 413 + 2*347 + 7*498 - 8*799 - 12*467

= -2860 KJ

Answer: -2860 KJ