Water forms according to the equation below:

2H2 (g) + O2 (g) - > 2H2O (g) ΔHrxn = - 483.64 kJ

How much energy is released during the formation of 1 mol H2O (g) ?

__kJ

241.82 kJ is released

Explanation:

The reaction indicates that 483.64 kJ of energy is released when TWO moles of H2O (g) is formed. You're looking to find the amount of energy released when only ONE mole of H2O forms, so that would be half the amount of energy released in the reaction (as one mole is a half of two).

483.64 / 2 = 241.82 kJ

So, your answer would be 241.82 kJ is released.