ΔHf of which of the following cannot be measured directly?
Correct answer: D. All of these options are correct
- A. Al2O3
- B. B2O3
- C. CCL4
- D. All of these options are correct
Explanation
Frankly speaking, We don't know the absolute enthalpy of a substance because we don't know where absolute Zero is. We can only deal with this calculation under relative terms so, we can only measure enthalpy differences between initial and final states.
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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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