# Lauren

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

1. 👍
2. 👎
3. 👁
4. ℹ️
5. 🚩
1. All elements have a delta Hf of zero at 1.0 atm and 25o C.

1. 👍
2. 👎
3. ℹ️
4. 🚩
2. So I need to find the Hf of each of those equations

1. 👍
2. 👎
3. ℹ️
4. 🚩
3. 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).

1. 👍
2. 👎
3. ℹ️
4. 🚩
4. Fe(s) is an element right

1. 👍
2. 👎
3. ℹ️
4. 🚩
5. yes.

1. 👍
2. 👎
3. ℹ️
4. 🚩

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