heat capacity at constant V and constant P

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Michael Du 1E
Posts: 117
Joined: Sun Sep 22, 2019 12:16 am

heat capacity at constant V and constant P

Postby Michael Du 1E » Wed Feb 05, 2020 10:38 pm

Can anyone please explain why q = delta U in the equation for the heat capacity at constant volume and why q = delta H in the equation for the heat capacity at constant pressure? Thank you

chemboi
Posts: 101
Joined: Sat Jul 20, 2019 12:16 am

Re: heat capacity at constant V and constant P

Postby chemboi » Wed Feb 05, 2020 11:26 pm

at constant volume, q = delta U because no work is being done in expansion, so w is zero. q+w = delta U, so only q is left over. If someone could clarify the second part, that would be great because I'm not sure :(

Adriana_4F
Posts: 74
Joined: Fri Sep 28, 2018 12:29 am

Re: heat capacity at constant V and constant P

Postby Adriana_4F » Thu Feb 06, 2020 12:13 am

The definition of Enthalpy (deltaH) is the amount of heat released or absorbed at a constant pressure, so qp and deltaH can be used interchangeably.


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