Standard Enthalpy

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Briana Yik 1H
Posts: 30
Joined: Fri Sep 28, 2018 12:20 am

Standard Enthalpy

Postby Briana Yik 1H » Thu Jan 31, 2019 12:56 pm

Can someone explain why standard enthalpy od O2 is zero? Thank you

Iris Bai 2K
Posts: 60
Joined: Fri Sep 28, 2018 12:18 am

Re: Standard Enthalpy

Postby Iris Bai 2K » Thu Jan 31, 2019 1:03 pm

The standard enthalpy of formation of O2 is 0, not the standard enthalpy (idk if that's even a thing). It's because oxygen is found naturally as a diatomic molecule, so it doesn't take energy to "form" it the way it's found in nature.

Nandhini_2K
Posts: 60
Joined: Fri Apr 06, 2018 11:03 am

Re: Standard Enthalpy

Postby Nandhini_2K » Thu Jan 31, 2019 1:07 pm

O2 is 0 at standard state. All diatomic elements such as N2, O2, H2, will be zero and any single element from the periodic table.

shaunajava2e
Posts: 66
Joined: Fri Sep 28, 2018 12:26 am

Re: Standard Enthalpy

Postby shaunajava2e » Thu Jan 31, 2019 2:43 pm

All elements in their standard states (oxygen gas, solid carbon in the form of graphite, etc.) have a standard enthalpy of formation of zero, as there is no change involved in their formation.

tierra parker 1J
Posts: 61
Joined: Fri Sep 28, 2018 12:17 am

Re: Standard Enthalpy

Postby tierra parker 1J » Thu Jan 31, 2019 7:04 pm

since 02 is normally found as a diatomic molecule so there is no need to form the molecule which gives a zero enthalpy of formation


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