Adding and subtracting properties
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Adding and subtracting properties
Can someone please explain why we do final minus initial when doing state properties?
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Re: Adding and subtracting properties
State properties are not dependent on the path taken to obtain that state. You do final minus initial with state properties because it does not matter the path taken to get to the final state, only the final and initial values matter.
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Re: Adding and subtracting properties
State properties only depend on the final and initial states. They only care about the destinations not the journey.
So for deltas like enthalpy (which is state dependent), to find it you do: Final state value - Initial state value. State dependent properties are only involved with total changes from start to finish, not in between.
So for deltas like enthalpy (which is state dependent), to find it you do: Final state value - Initial state value. State dependent properties are only involved with total changes from start to finish, not in between.
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Re: Adding and subtracting properties
We can add the final and initial values for state properties since we don't care about what goes on in the middle of the process. Work and energy are different in which we want to look at how much is being used and wasted on the journey.
Re: Adding and subtracting properties
Can someone give me an example of a property that is dependent on the path taken besides work?
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Re: Adding and subtracting properties
ShastaB4C wrote:Can someone give me an example of a property that is dependent on the path taken besides work?
Heat is also a path function because the energy transferred as heat depends on how that change occurred.
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Re: Adding and subtracting properties
State properties, as said above, are not dependent on the "in between"; rather, we only focus on the initial and final measurements to make calculations and assumption.
State properties include energy, pressure, volume, temperature, density and heat capacity
Non state properties (or properties that are dependent on the "in between") include work and heat.
State properties include energy, pressure, volume, temperature, density and heat capacity
Non state properties (or properties that are dependent on the "in between") include work and heat.
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