Indicate whether the following statements are true or false for a reversible isothermal process: (a) q=t(∆s). (b) ∆u=0.(c) the entropy change of the system is always zero.(d) the total entropy change of the system and the surroundings is zero.(e) q=w.(f) the entropy change of the environment is negative.(g) the total entropy change of the system and the surroundings is negative.

A)True

B)True

C)False

D)True

E)True

F)False

G)False

Explanation:

Reversible -isothermal process:

 We know that a process called reversible if when this process will be revers then it will not leave any effect on surrounding will return in original state.

A process is called isothermal process if ,initial and final temperature is same.

A)

Q=TΔS

Yes it is true for reversible and isothermal process.

B)

ΔU= 0

For isothermal process  ΔU= 0.

It is true only for ideal gas.

C)The entropy change of system can be positive ,negative .

So it is false.

D)

We know that

Entropy change of universe =  Entropy change of system + Entropy change of surrounding.

For reversible process

Entropy change of universe =0

So it is true.

E)

From first law

Q= ΔU + W

For isothermal process  ΔU= 0.  (only for ideal gas)

⇒Q= W

So it is true.

F)

The entropy change of surrounding can be positive ,negative .

So it is false.

G)We know that total entropy change of universe given as

Entropy change of universe =  Entropy change of system + Entropy change of surrounding.

For reversible process

Total  Entropy change of universe =0

So it is false.

diy

explanation:

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