What is the definition of the standard enthalpy of formation?
Answer and explanation
Correct answer: A. The enthalpy change when one mole of a compound forms from its elements in standard states
- Step 1: Standard conditions are 100 kPa and a stated temperature (usually 298 K). Answer: The enthalpy change when one mole of a compound forms from its elements in standard states. Why not the others: burning is combustion; forming gaseous atoms is atomisation; forming water from acid and alkali is neutralisation.
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