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AP EAMCET202418 May 2024Morning ShiftChemistryThermodynamics (C)Actual

Identify the incorrect statements from the following I. S _ system = ( S _ total + S _ surr. ) II. A (l) A ( s ) : for this process entropy change decreases III. Entropy units are JK mol ⁻¹

Options

  1. AI, III only
  2. BI, II only
  3. CI, II, III
  4. DII, III only

Correct answer

A. I, III only

Step-by-step solution

(I) The total entropy change ( S _ total ) for the system and surrounding of a spontaneous process is given by S _ total = S _ sys + S _ surr (II) A ( l ) A ( s ) : for this process liquid to solid randomness or disorder in the system decreases. So entropy change decreases. entropy will increases in following cases. (i) A ( s ) A ( l ) (ii) A ( l ) A (g) (iii) A ( s ) A ( g ) (iv) On increasing temperature S will increase (v) On decreasing pressure, S will increases. (III) Unit of entropy (S) is JK ⁻¹ ~mol ⁻¹ or ca

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