JEE Advanced · ChemistryEasy
The standard enthalpy of formation of an element in its most stable state at is:
- A.Positive
- B.Negative
- C.Zero
- D.Undefined
Show correct answer & step-by-step solution
Correct answer: C — Zero
Solution
- The standard enthalpy of formation is defined as the enthalpy change when one mole of a substance is formed from its elements.
- Elements in their most stable standard state are already in their reference form.
- Therefore, no enthalpy change is required to form them from themselves.
- The value is defined as .
- Hence the answer is (C).
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