All isothermal and adiabatic processes are reversible when carried out very slowly.
Is it true for the isobaric process too? As isobaric process can also be carried out very slowly.
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1$\begingroup$ Carrying out the operation slowly is part of what is typically required. But, the absence of kinetic friction is also necessary. And in some cases, like acceleration of a rigid body without friction, the operation does not have to be carried out very slowly (i.e., as long as no dissipative forces are involved). $\endgroup$– Chet MillerJun 29, 2019 at 12:37
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Reversible processes are processes in which the thermodynamic system changes from one state to another such that it stays in equilibrium throughout the change. Usually you can achieve this by making the change arbitrarily slow such that you never really 'break' away from equilibrium or the system stays arbitrarily close to equilibrium state. Of course what is 'slow' depends on the system under consideration.
Isobaric processes are processes that occur under constant pressure. So if we are able to control the change in other macroscopic parameters of the system such that they change slow enough, yes you can carry out isobaric process slowly and reversibly.
Say you are heating an ideal gas in some container whose volume we can control. We know that the heat gained by the system will increase temperature and pressure of the gas. And at equilibrium we know that it obeys the ideal gas equation
$$P = \frac{nRT}{V}$$
So if you are heating it slow enough, the slight change in pressure can be offset by proportionally adjusting the volume in such a way that the overall pressure remains a constant. The process being slow ensures that the system is close to equilibrium state and varying the volume will ensure that the system is at constant pressure and thus isobaric.
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$\begingroup$ Can we say that an isobaric process would be reversible if we heat the gas very slowly? $\endgroup$ Jun 26, 2020 at 9:44