The enthalpies for the following reactions at 25°C are given.
12 H2(g) + 12 O2(g)→OH(g); △H = 10.06 K cal
H2(g)→2H(g); △H = 104.18 K cal
O2(g)→2O(g); △H = 118.32 K cal
Calculate the OH bond energy in the O - H group
-101.19 K col
H(g) + O(g) → O - H(g) Required equation
Given: 12 H2(g) + 12O2(g)→OH(g); △H=+10.06 K cal
H(g)→12H2(g);△H=−52.09 K cal
O(g)→ 12 O2(g); △H = −59.16 K cal
Adding them we get H(g) + O(g)+ (OH)(g) △H = −101.19 K cal