210k views
4 votes
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)?
How much energy must be added to the reaction:
2H₂O(g) → 2H₂(g) + 2O₂(g)?

User Drt
by
7.5k points

2 Answers

7 votes
Answer: 3 mols released
User Amolk
by
8.0k points
6 votes

Answer:

483.64 kJ

Step-by-step explanation:

The given reaction is:

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

The reaction indicates that 483.64 kJ of energy is released during the formation of 2 moles of H₂O(g). Therefore, to find the energy released during the formation of 1 mole of H₂O(g), we can divide the given value by 2:

Energy released per mole of H₂O(g) = -483.64 kJ / 2

= -241.82 kJ

Hence, 241.82 kJ of energy is released during the formation of 1 mole of H₂O(g).

Now, let's consider the reverse reaction:

2H₂O(g) → 2H₂(g) + O₂(g)

To find the energy that must be added to this reaction, we need to consider the energy change in the reverse direction. Since the given value (-483.64 kJ) represents the energy change in the forward direction, we need to reverse the sign:

Energy change in the reverse direction = -(-483.64 kJ)

= 483.64 kJ

Therefore, 483.64 kJ of energy must be added to the reaction:

2H₂O(g) → 2H₂(g) + O₂(g)

User Zidane
by
8.3k points