The value of the enthalpy of formation of H⁺ and O₂⁻ ions from Hydrogen and Oxygen at 25°C is:H₂O(l) → H⁺(aq) + OH⁻(aq) ΔH = 57.32 kJH₂(g) + 1/2 O₂(g) → H₂O(l).
Correct answer: A. -228.88 KJ/mol
- A. -228.88 KJ/mol
- B. -343.52 KJ/mol
- C. +228.88 KJ/mol
- D. -22.88 KJ/mol
Explanation
For the formation of H⁺ ions from hydrogen and O₂⁻ ions from oxygen, the standard enthalpy of formation at 25°C is -228.88 KJ/mol. This is because the process involves breaking bonds in the reactants, often resulting in an energy release. Therefore, the negative sign indicates an exothermic process.
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About Thermochemistry and Energetics of Chemical Reactions
Thermochemistry measures energy changes in chemical reactions and distinguishes exothermic from endothermic processes. Work covers systems, surroundings and state functions, internal energy, the first law of thermodynamics, enthalpy and Hess's law, including the sign conventions used when heat enters or leaves a system.
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