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H-h 336 c-h 414 c-c 347 c-o 360 o-h 464 o=o 498 c=o 736 c=o in CO₂⁺ 799 part a ethanol is a possible fuel. use average bond energies to calculate Δhrxn for the combustion of ethanol. ch3ch2oh(g) 3 o2(g) → 2 CO₂⁺(g) 3 h2o(g) express your answer as an integer.

User Cong Tran
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Final answer:

The enthalpy of combustion of 1 mole of ethanol is -1377 kJ/mol.

Step-by-step explanation:

The balanced equation for the combustion of ethanol to CO₂(g) and H₂O(g) is:

C₂H₅OH(g) + 3O₂(g) → 2CO₂(g) + 3H₂O(g)

To calculate the enthalpy of combustion of 1 mole of ethanol, we need to use the bond energies. Since we don't have the bond energies for ethanol, we can approximate it using the average bond energies.

The average bond energies are as follows:

C-C bond: 347 kJ/mol

C-H bond: 414 kJ/mol

O-H bond: 464 kJ/mol

Using these bond energies, we can calculate the enthalpy of combustion:

(2 x C-C bond) + (6 x C-H bond) + (3 x O=O bond) - (2 x O-H bond) - (6 x C=O bond)

Substituting the values:

(2 x 347) + (6 x 414) + (3 x 498) - (2 x 464) - (6 x 736) = -1377 kJ/mol

The enthalpy of combustion of 1 mole of ethanol is -1377 kJ/mol.

User Pitabas Prathal
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