Question

For the reaction,
$ 2H_{2}(g) +O_{2} (g) \to 2H_2O(g) $ , $ \Delta H^{\circ} = -573.2\,kJ $
The heat of decomposition of water per mole is

• A. $ 286.6\,kJ $
• B. $ 573.2\,kJ $
• C. $ -28.66\,kJ $
• D. zero

Answer 1

Answer: (A)

Heat of decomposition of water is

$H _{2} O (g) \longrightarrow H _{2}(g)+\frac{1}{2} O _{2}(g)$

$\Delta H =\frac{+573.2}{2}$

$= 286.6 kJ / mol$