Which one of the following processes has ∆H positive?
Correct answer: A. lonization energy
- A. lonization energy
- B. Electron affinity
- C. Combustion
- D. Exothermic reaction
Explanation
The answer is ionization energy.Ionization energy is the energy required to remove an electron from an atom or molecule in the gaseous state. The enthalpy change (∆H) for ionization energy is positive because energy is required to remove the electron.
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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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