Standard Enthalpy Formation of an element

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Daisylookinland
Posts: 46
Joined: Fri Sep 28, 2018 12:28 am

Standard Enthalpy Formation of an element

Postby Daisylookinland » Mon Jan 28, 2019 1:13 pm

Why is it that the standard enthalpy formation of an element in its most standard form is zero?

Nicklas_Wright_1A
Posts: 60
Joined: Fri Sep 28, 2018 12:23 am

Re: Standard Enthalpy Formation of an element

Postby Nicklas_Wright_1A » Mon Jan 28, 2019 1:39 pm

Standard enthalpy of formation is the enthalpy used to create a compound from its elemental components. Since the elemental components are already in the elemental form, it does not take any enthalpy to create them from the elemental form.

Jocelyne Milke 1G
Posts: 73
Joined: Fri Sep 28, 2018 12:25 am

Re: Standard Enthalpy Formation of an element

Postby Jocelyne Milke 1G » Sun Feb 03, 2019 2:35 pm

The element is already in its most stable form so the standard enthalpy of formation is zero

pamcoronel1H
Posts: 45
Joined: Fri Sep 28, 2018 12:25 am

Re: Standard Enthalpy Formation of an element

Postby pamcoronel1H » Sun Feb 03, 2019 6:46 pm

The standard enthalpy of formation is defined by the enthalpy per mole of formula units of a reaction with STABLE elements.

So, for example, O2 is made up of O and O, which is a stable reaction and so its a "null reaction".

Rami_Z_AbuQubo_2K
Posts: 89
Joined: Thu Jun 07, 2018 3:00 am

Re: Standard Enthalpy Formation of an element

Postby Rami_Z_AbuQubo_2K » Sun Feb 03, 2019 7:28 pm

Does the standard enthalpy of 0 only apply to diatomic molecules like H, O, F, Cl, Br, I, N?


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