What energy change is associated with the reaction to obtain one mole of H2 from one mole of water vapor? The balanced equation is 2 H2O(g) - 2 H2(g) + O2(g)and the relevant bond energies are

Question

What energy change is associated with the reaction to obtain one mole of H2 from one mole of water vapor? The balanced equation is 2 H2O(g) -> 2 H2(g) + O2(g)and the relevant bond energies are
H-H : 436 kJ/mol; H-O : 467 kJ/mol;
O-O : 146 kJ/mol; O=O : 498 kJ/mol.
1. +249 kJ
2. −436 kJ
3. +425 kJ
4. −425 kJ

e · Accepted Answer

the answer is 246

DrBob222 · Answer

It appears to me that we must break 4 OH bonds for the two moles H2O and form 2 H-H bonds and 2 O-O bonds. The difference between (sum bond energies reactants)-(sum bond energies products) = delta H rxn for 2 moles H2O and 2 moles H2. Therefore, divide that number by 2. Check my thinking.

lisa · Answer

the answer i -436

ally procket · Answer

lisa that isnt the right answer lol... it is actually -436... stupiddddd