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AP EAMCET20225 Jul 2022Morning ShiftChemistryThermodynamics (C)Actual

Identify the correct statements from the following. I. At 0 ~K , the entropy of pure crystalline materials approach zero. II. Entropy for the process, H ₂ O ( l ) H ₂ O ( g ) decreases. III. Gibb's energy is a state function.

Options

  1. AI, II, III
  2. BI, III
  3. CII, III
  4. DI, II

Correct answer

B. I, III

Step-by-step solution

At 0 ~K , the entropy of pure crystalline materials is zero. The statement (I) is correct as entropy approach zero, at absolute zero. Statement (II) entropy for the process, H ₂ O (l) H ₂ O ( g ) decreases is incorrect as entropy increases. The degree of randomness when water vaporises to gaseous state increases. (III) Gibbs' energy is a state function is correct as the Gibbs' free energy depends on initial and final state only. Hence, statement (I) and (III) are correct.

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