When to use Standard enthalpies of formation

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Sanjana Munagala_1j
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When to use Standard enthalpies of formation

Postby Sanjana Munagala_1j » Fri Jan 24, 2020 8:20 pm

So when dealing with standard enthalpies of formation, we are looking at reactions at standard conditions. Does this mean we can't use this method for reactions that are not in standard conditions. If we can, how can we account for the difference. Please let me know!
Thanks!

Brandi 2C
Posts: 52
Joined: Thu Feb 28, 2019 12:15 am

Re: When to use Standard enthalpies of formation

Postby Brandi 2C » Fri Jan 24, 2020 10:21 pm

I don't think you can do this for problems that are not set in standard condition because the equation for the method requires delta H ° and that only applies to bonds in standard condition.

andrewcj 2C
Posts: 102
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Re: When to use Standard enthalpies of formation

Postby andrewcj 2C » Sat Jan 25, 2020 1:31 am

To account for non-standard conditions, you just add the enthalpy changes required to get the reactants into their respective states in the conditions given.

Jared Khoo 1G
Posts: 107
Joined: Wed Sep 18, 2019 12:16 am

Re: When to use Standard enthalpies of formation

Postby Jared Khoo 1G » Sat Jan 25, 2020 3:06 pm

The standard enthalpies of formation are usually given at STP therefore it would be different under nonstandard conditions.


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