Standard Enthalpy of Formation
Posted: Thu Jan 14, 2016 2:45 pm
Lavelle writes in his course reader that the standard enthalpy of formation of an element in its most stable form is zero. He also mentions later in the example that oxygen gas is in its most stable form. How do you know if an element is in its stable form or not?
Re: Standard Enthalpy of Formation
Posted: Thu Jan 14, 2016 5:48 pm
For most elements, the most stable form is just a single atom. However, some elements are most stable in a diatomic for such as hydrogen, nitrogen, fluorine, oxygen, iodine, chlorine, bromine. I think you just have to memorize which elements are most stable in a diatomic form.
Here is a nice mnemonic I found on the internet
Have No Fear Of Ice Cold Beer
Hope this helps :)