Chemistry Graph of several thermodynamic processes

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The discussion revolves around the interpretation of a thermodynamic graph depicting various processes. A key question raised is whether state D would have the same pressure as state A if the process from A to D was not included. Participants clarify that in a reversible system, pressure and volume can be returned to their original states, provided temperature remains constant. Misinterpretations of the graph, particularly regarding the direction of arrows and the nature of isochoric and isobaric processes, are addressed. Ultimately, the consensus is that the pressure at state A influences the final state D, especially considering the isochoric process involved.
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Homework Statement
Graph these processes on a PV graph : Isothermal expansion from state A to B, isochoric pressure increment from B to C,
isothermal contraction from C to D, isobaric contraction from D to A.
Relevant Equations
!!!
I graphed it similar to this

IMG_20240314_204917.jpg


My query is say if the last process wasn't mentioned, I.e the process from A TO D, would the state D have the same pressure as state A then? In thermodynamics for a reversible system we say that if it undergoes a change in pressure volume the exact pressure and volume can he achieved when we reverse it, considering the temperature is constant. But here since we underwent an isochoric process from B to C and then reversed it, would it have ended at the same pressure of A if not for the last condition?
 
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Did you post the picture you intended to post?
I see the arrows going in the wrong direction, isochoric (at the same volume) and isobaric (at the same pressure) misinterpreted, etc...
 
BvU said:
Did you post the picture you intended to post?
I see the arrows going in the wrong direction, isochoric (at the same volume) and isobaric (at the same pressure) misinterpreted, etc...
Oh, sorry my question is typed wrong

[Post edited by a Mentor]
 
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BvU said:
Did you post the picture you intended to post?
I see the arrows going in the wrong direction, isochoric (at the same volume) and isobaric (at the same pressure) misinterpreted, etc...
All fixed! Please give it another read i interchanged D & B by mistake
 
BvU said:
Did you post the picture you intended to post?
I see the arrows going in the wrong direction, isochoric (at the same volume) and isobaric (at the same pressure) misinterpreted, etc...
Hi, if you have some free time, please consider clearing my doubt. Thankyou.
 
Back from a short vacation, but I think we need more expertise. @Chestermiller ?
 
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Fwiw: CD is an isothermic volume reduction down to a particular pressure. Whoever executes the cycle can choose that pressure; since DA is supposed to be isochoric, the choice of P at A makes sense.
 
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BvU said:
Back from a short vacation, but I think we need more expertise. @Chestermiller ?
It seems to me the graph in post #1 is correct, except BC should be vertical.
 
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BvU said:
Fwiw: CD is an isothermic volume reduction down to a particular pressure. Whoever executes the cycle can choose that pressure; since DA is supposed to be isochoric, the choice of P at A makes sense.
That was the doubt if pressure would have remained the same if the last isochoric condition wasnt there. Got it. thanks
 
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