Units for enthalpy

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Clarissa Cabil 1I
Posts: 66
Joined: Fri Sep 28, 2018 12:19 am

Units for enthalpy

Postby Clarissa Cabil 1I » Sun Feb 10, 2019 6:23 pm

I am a bit confused on which units I should use for enthalpy.

The book mentions how standard enthalpies of formation are in kJ.mol-1 and standard enthalpies of reaction are in kJ, but some of the answers for the homework switch the two.

Can anyone clarify what units we should use for enthalpy, and when we should use those units?

arif_latif_2G
Posts: 60
Joined: Fri Sep 28, 2018 12:23 am

Re: Units for enthalpy

Postby arif_latif_2G » Sun Feb 10, 2019 6:37 pm

According to my TA, Jack, both KJ or J work.

Jaqueline Monreal 2L
Posts: 57
Joined: Fri Sep 28, 2018 12:28 am

Re: Units for enthalpy

Postby Jaqueline Monreal 2L » Sun Feb 10, 2019 7:38 pm

you can use either one

404982241
Posts: 47
Joined: Fri Sep 28, 2018 12:17 am

Re: Units for enthalpy

Postby 404982241 » Sun Feb 10, 2019 10:27 pm

Joule is the SI unit but sometimes it makes more sense to use Kilo Joules for convince reasons.

Elizabeth Kim 4E
Posts: 60
Joined: Fri Sep 28, 2018 12:29 am

Re: Units for enthalpy

Postby Elizabeth Kim 4E » Mon Feb 11, 2019 12:07 pm

I think the SI unit is kJ and is used as the final answer on most of the answer keys, so it would be safer to put the final answer in kJ

Emma Scholes 1L
Posts: 62
Joined: Fri Sep 28, 2018 12:18 am

Re: Units for enthalpy

Postby Emma Scholes 1L » Mon Feb 11, 2019 12:13 pm

You can use either J or kJ. Both will be accepted on the test, but when the amount of J is above 1000, it is usually written in kJ.

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

Re: Units for enthalpy

Postby Nandhini_2K » Mon Feb 11, 2019 1:55 pm

Either J or KJ. The final answer in J can be turned to KJ by simply dividing it by 1000.


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