Question

expression for entropy change for reversiable process​

Answer 1

Answer:

ΔSsurr=−qrevT. Thus no change in ΔSuniv has occurred. In the initial state (top), the temperatures of a gas and the surroundings are the same. During the reversible expansion of the gas, heat must be added to the gas to maintain a constant temperature.

Answer 2

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Thus the entropy change of the universe during reversible processes is zero. we see that the entropy change of a system during for a reversible, adiabatic process is zero.