The one that does not have a standard enthalpy of formation equal to zero at 25 °C and 1.0 atm is a. H₂O(l).
The standard enthalpy of formation is defined as the change in enthalpy when one mole of a substance in the standard state (1 atm of pressure and 298.15 K) is formed from its pure elements under the same conditions.
By convention, the standard enthalpy of formation of simple substances in their most stable form is zero.
Let's consider which of the following does not have a standard enthalpy of formation equal to zero at 25 °C and 1.0 atm.
- a. H₂O(l). It is a compound, not a simple substance, so its standard enthalpy of formation is not zero.
- b. F₂(g). It is the most stable form of a simple substance so its standard enthalpy of formation is zero.
- c. Al(s). It is the most stable form of a simple substance so its standard enthalpy of formation is zero.
- d. H₂(g). It is the most stable form of a simple substance so its standard enthalpy of formation is zero.
The one that does not have a standard enthalpy of formation equal to zero at 25 °C and 1.0 atm is a. H₂O(l).
Learn more: https://brainly.com/question/25140395
