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JEE Advanced2012ChemistryThermodynamics (C)Actual

For an ideal gas, consider only P-V work in going from an initial state X to the final state Z . The final state Z can be reached by either of the two paths shown in the figure. Which of the following choice(s) is (are) correct? [Take S as change in entropy and w as work done].

Options

  1. AS _ x z = S _ x y + S _ y z
  2. Bw _ x z = w _ x y + w _ y z
  3. Cw _ x y z = w _ x y
  4. DS _ x y z = S _ x y

Correct answer

A. S _ x z = S _ x y + S _ y z

Step-by-step solution

S_ X Z = S_ X Y + S_ Y Z [Entropy is a state function, hence additive] w_ X Y Z =w_ X Y [Work done in Y Z is zero because it is an isochoric process].

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