heat and state function

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Jasmine Lam 1I
Posts: 20
Joined: Fri Sep 25, 2015 3:00 am

heat and state function

Postby Jasmine Lam 1I » Fri Jan 08, 2016 11:28 am

Why is heat not a state function but enthalpy is?
What are state functions?
Thanks :)

Charlene Tang 1B
Posts: 25
Joined: Fri Sep 25, 2015 3:00 am

Re: heat and state function

Postby Charlene Tang 1B » Fri Jan 08, 2016 11:35 am

Heat is not a state function because it depends on the pressure during heating/cooling and not just the initial and final temperatures and pressure, while enthalpy is measured at constant pressure.

State functions are step independent functions and only the initial and the final values matter, not the steps.

Hope that helps!

Shrita Pendekanti 4B
Posts: 22
Joined: Fri Sep 25, 2015 3:00 am

Re: heat and state function

Postby Shrita Pendekanti 4B » Fri Jan 08, 2016 11:43 am

A state function describes the equilibrium state of a system. In this case, enthalpy describes a thermodynamic system, irrespective of the paths each part of the system took to arrive at its current state. Heat is not a state function because it is a form of energy being transitioned as a cause of change (think of it as part of one of the paths you're allowed to ignore). Hope this helps!


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