# Lauren

posted by .

Which of the following has a standard enthalpy of formation value of zero at 25 degrees C and 1.0 atm

A. Fe(s)
B. Fe2O3(s)
C. FeSO4(s)
D. FeSO4(aq)
E. FeS3(s)

and what is enthalpy or how do you find it

• Lauren -

All elements have a delta Hf of zero at 1.0 atm and 25o C.

• Lauren -

So I need to find the Hf of each of those equations

• Lauren -

Absolutely not.
All ELEMENTS have a standard heat of formation of zero at 1.0 atom and 25 degrees C. Which of the 5 answers listed is an ELEMENT (the other four are, of course, compounds).

• Lauren -

Fe(s) is an element right

• Lauren -

yes.

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