Answer:
H
2
(g)+
2
1
O
2
(g)⟶H
2
O(l)ΔHr−285.8=−
2
571.6
H
2
O(l)⟶H
2
O(g)+40.6
∴ H
2
O(g)+
2
1
O
2
(g)⟶H
2
O(g)−245.2 KJ/mol
Let the average OH bond energy in H
2
O be x
∴ −245.2=(435+244.8)−(2x)
⇒ 2x=435+244.8+245.2
⇒ x=
2
925
=462.5 KJ/mol
H−H+
2
1
O−O→H−O−H
Step-by-step explanation: