What is the concept behind 'irreversible adiabatic process' ? Why is the expression for work done in this case different from that when it is reversible?
I need some clarification on the following points on the reversible and irreversible reactions.
In the examples cited in textbooks, for reversible reaction, isothermal expansion and compression are given. But the adiabatic exp and comp are not given.
Why is it not included in the list...
Hopefully somebody can help me with this. I have a final exam next week, and the textbook we use along with my professor didn't do a good job explaining what happens in irreversible reactions.
More specifically, what differences are there between reversible and irreversible processes of...
I know work for reversible + isothermal is w=nRTln(v2/v1) but what about irrev? I see the equation W=P(delta V) used all the time. Is this the correct one to use? or is there another equn for irreversible work for a gas?
THanks
My textbook tries to prove that for Entropy of Irreversible Process > 0 by using the example of irrev expasion into a vacuum which doesn't make sense to me.
If work is = 0 then no heat is exchanged between the sys and surrounding so qsurr = 0
s(uni) = s(sys) + 0
since S(sys)=qirr/t and no...
Our laws that describe entropy to be irreversible using our macroscopic experiments in which they always come out with a certain outcome. However, I think there is no such thing as an irreversible process on a quantum level and the quantum level is the stronghold of everything. Everything is...
Homework Statement
State whether the thermodynamic quantities q (heat), w (work), ΔU (internal energy) and ΔS (entropy) are greater than, equal to, or less than zero when one mole of an ideal gas expands irreversibly and against a constant external pressure of zero.
Homework Equations...
Homework Statement
Calculate the entropy for an irreversible adiabatic expansion of an ideal gas which goes from (Vi, Pi) = (9.01L, 3.00 bar) to (Vf, Pf) = (15.44L, 1.50 bar)Homework Equations
\DeltaS = \int dq_{reversible}/T
The Attempt at a Solution
I understand that entropy is a state...
Homework Statement
A gas expands through an adiabatic irreversibly process, from (P1, V1, T1) to (P2, V2, T2). In a PV graphic, localize both states 1 and 2, and the adiabats that pass through each of them.
The Attempt at a Solution
It's a theory question. I can locate 1 anywhere I...
In trying to understand the underlying mechanics of irreversible processes, I came up with four mechanical asymmetries that seemed relevant to describe energy transfer through the bulk motion of a frictionless piston that divides a cylinder with two gasses of same pressure but different...
Here is a news release from the US Geological Survey.
I've copied some parts of it, but please read the entire release before commenting.
http://www.usgs.gov/newsroom/article_pf.asp?ID=2326
In brief, there are lots of uncertainties and potentials for climate change to impact
the role of...
Hi everybody.
I give you an example to clarify my question:
a NAND gate is irreversible becuase you can not find inputs from outputs and this is because of one bit is lost in output ( Antropy will increase ).the number of inputs and output are not the same in NAND gate.
ok...now my question...
I am confused about the entropy change for reversible and irreversible cycles. I know entropy is a state function, so for cycles, the entropy change within the system should be 0, since the process ends up in the same state as the beginning. So does this mean that the entropy change for the...
Suppose that one mole of a monatomic perfect gas at 27°C and 1.00 atm pressure
is expanded adiabatically (i.e. no heat transfer, so that the temperature must fall) in two
different ways: (a) reversibly, to a final pressure of 0.5 atm, and (b) against a constant
external pressure of 0.5 atm...
Hello Lords of Physics,
sorry for pestering you guys again but these days a question about irreversibility is pestering me , my question is
Why we say that irreversibility in process is due to finite tempreture difference ?
so if there is finite temp diff. why process is not reversible...
work done in an reversible process is easy to find we have the function of P internal bt when it comes to irreversible process then how do we find work done by the gas or on it and if ur answer is (sry i am new to forum i don't know how to use the features) [ integration p external dv] then...
Homework Statement
Consider a gas with adjustable volume V, and diathermal walls, embedded in a heat bath of constant temperature T, and fixed pressure P. The change in the entropy of the bath is given by:
delta S_bath = delta Q_bath/T = -deltaQ_gas/T = -1/T (delta E_gas + P deltaV_gas)...
Homework Statement
Can entropy change be zero for a closed system in an irreversible process? If yes under what conditions? Thanks!
Homework Equations
The Attempt at a Solution
Can entropy change be zero for a closed system in an irreversible process? If yes under what conditions? Thanks!
Is it ture that it would be zero in an adiabatic, process carried in consant temperature?
This question came some time back in Stony Brooks exam. I have the solution also. But i am having some conceptual doubts. Can someone help me please.
The question is:
Consider ‘n’ moles of an ideal monoatomic gas placed in a vertical cylinder. The top of the cylinder is closed by a piston...
Hey everyone =) This is my first post here but I've been lurking for a while.
Anyway, so i am taking this physical chemistry class and I can't seem to solve this problem. I think it is still a physics problem.
Anyway, it goes like this:
small amount of moles of steam (.83 moles) @ 100...
I am having trouble with these questions. Can anyone help please
1. How is it possible to have an isentropic process which is irreversible?
2.Why is it desirable to have processes which are less irreversible?
3. Is the expression for the 1st law of thermodynamics for a closed system...
A balloon featured with a negligible thermal capacity contains V_{l}=3l of ideal gas and is immersed in a lake (thermal bath) at the depth of h_{l}=10m beneath the lake surface. If it is brought to the depth of h_{l}=3m, how much is the heat exchange?
Hi,
I was wondering something. Exactly what is meant by a thermodynamically reversible/irreversible process? What are their relation to spontaneous processes? These concepts seem to be fundamental to the understanding of the second law, but textbooks (including the industry standard Atkins...
It is stated that the change in entropy of an isolated system during an irreversible process is > 0; while for a reversible process, it is = 0.
An isochoric process has a change in entropy given by : nCv(Pf/Pi). Does this mean that it is an irreversible process?
ARen't isochoric processes...
Hello. I'm still confused about the thermodynamics involved in magnetic domain wall motion. I understand the different pinning mechanisms, but I fail to see how this phenomena leads to Irreversible losses during magnetic hysterisis. For instance, how can precipitate which can put a section of a...
Question:
2 moles of a monatomic ideal gas at an initial pressure of 20 atm and a temperature of 450K undergo a rapid (adiabatic) free expansion from a small vessel into a vessel of 40 times greater volume. Find
i) the change in temperature and
ii) the increase in entropy
The first part I...
Hi,
I'm working on a problem of the thermal stability of a protein. Conventionlly, people compare protein thermal stability in terms of the Gibbs free energy difference between the native and unfolded state. So if it reversibly falls apart, then for N <==> U, DG(N-U) is accessed from the...
Hi,
I'm working on a problem of the thermal stability of a protein. Conventionlly, people compare protein thermal stability in terms of the Gibbs free energy difference between the native and unfolded state. So if it reversibly falls apart, then for N <==> U, DG(N-U) is accessed from the...