Question

Use the reaction equation and bond energies to answer the question.2H20 - 2H2 + 02H-O: 467 kJ/molH-H: 432 kJ/molO=0: 495 kJ/molWhat is the total energy of the reaction? Is this an endothermic or exothermic reaction? okay

Answer 1

The total energy of the reaction is 2,237kJ/mol.

The reaction is endothermic.

Step-by-step explanation:

To calculate the total energy of the reaction, it is necessary to subtract each bond energy in the reaction:

- Bonds broken (to the left of the arrow):

`\begin{gathered} \\ 2H_2O:2*\left(467kJ/mol+467kJ/mol\right)=1868kJ \\ 2H_2:2*(432kJ/mol)=864kJ/mol\text{ } \\ \\ \end{gathered}`

Total broken bonds: 2,732kJ/mol

- Bonds made (to the right of the arrow):

`O_2:495kJ/mol`

Total made bonds: 495kJ/mol

Finally, we have to subtract the total broken bonds minus total made bonds:

`\begin{gathered} \text{ Total bond energy: 2,732kJ/mol-495kJ/mol} \\ \text{ Total bond energy: 2,237kJ/mol} \end{gathered}`

So, the total energy of the reaction is 2,237kJ/mol, and the positive sign means that the reaction is endothermic.