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heat capacity at constant V and constant P

Posted: Wed Feb 05, 2020 10:38 pm
by Michael Du 1E
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

Re: heat capacity at constant V and constant P

Posted: Wed Feb 05, 2020 11:26 pm
by chemboi
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 :(

Re: heat capacity at constant V and constant P

Posted: Thu Feb 06, 2020 12:13 am
by Adriana_4F
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.