enthalpy of formation

[Mariane Sanchez 1E]

why is the standard enthalpy of formation of an element in its most stable form zero? does that mean it doesn't release energy when it is formed?

[Joyce Lee 1C]

I may be wrong but I think the standard enthalpy of formation of an element in its most stable form is zero because it's defined that way. We can't measure enthalpy and can only measure changes in enthalpy, so scientists need a baseline so the enthalpy of other elements can be defined relative to the standard enthalpy of formation.

[Ava Harvey 2B]

If I remember correctly from lecture, in the case of natural elements in their most stable state, no change in enthalpy takes place because the reactants and the product are exactly the same. The element is already formed, so a formation reaction is not necessary. Thus, the standard enthalpy of formation is zero. Hope this helps!