Enthalpy units

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Rose_Malki_3G
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Enthalpy units

Postby Rose_Malki_3G » Fri Jan 22, 2021 4:09 pm

Are the units of ΔH⊖rxn always just Kj whereas the units of ΔH⊖f always Kj/mol?

Nicole Huang 3F
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Re: Enthalpy units

Postby Nicole Huang 3F » Fri Jan 22, 2021 4:11 pm

Yeah, the units of ΔH⊖f are always in kJ/mol, and ΔHrxn are always in kJ (no moles bc its a overall reaction total).

Joshua Swift
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Re: Enthalpy units

Postby Joshua Swift » Fri Jan 22, 2021 4:38 pm

All enthalpy values will usually be given in kJ/mol unless it is for the overall reaction.

Gillian Gabrielsen2F
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Re: Enthalpy units

Postby Gillian Gabrielsen2F » Fri Jan 22, 2021 6:26 pm

ΔHf is kJ/mol because it's the enthalpy required to form a mole of a particular substance. ΔHrxn is just the enthalpy of the overall reaction. Enthalpy is just a measure of the energy released/absorbed as heat while at a constant pressure, hence why kJ is used.

Aayushi Jani 3A
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Re: Enthalpy units

Postby Aayushi Jani 3A » Fri Jan 22, 2021 6:47 pm

Yes, the units for ΔHf are kJ/mol while the units for ΔHrxn are just kJ (since it is representing the total of the overall reaction).

Ariel Guan 1H
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Re: Enthalpy units

Postby Ariel Guan 1H » Sat Jan 23, 2021 12:27 am

ΔH⊖f is in kJ/mol
ΔHrxn is kJ

Inderpal Singh 2L
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Re: Enthalpy units

Postby Inderpal Singh 2L » Sat Jan 23, 2021 1:15 am

ΔHf is in kJ/mol and ΔHrxn is in kJ.

Kyle Dizon 3A
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Re: Enthalpy units

Postby Kyle Dizon 3A » Sat Jan 23, 2021 10:21 am

Yes the units will always be kj/mol unless it is the ΔH⊖rxn because that is the overall reaction of enthalpy.


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