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NEETChemistryThermodynamics (C)

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): The freezing of liquid water to solid ice is a spontaneous process at 263 K . Reason (R): For the freezing of water, both H and S are negative, and at 263 K , the magnitude of enthalpy change is less than the magnitude of T S ( | H| In the light of the above statements, choose the most appropriate

Options

  1. ABoth (A) and (R) are correct and (R) is the correct explanation of (A)
  2. BBoth (A) and (R) are correct but (R) is not the correct explanation of (A)
  3. C(A) is correct but (R) is not correct
  4. D(A) is not correct but (R) is correct

Correct answer

C. (A) is correct but (R) is not correct

Step-by-step solution

Assertion (A) is correct: The freezing point of water is 273 K . At any temperature below 273 K (such as 263 K ), the freezing of liquid water into solid ice is a spontaneous process. Reason (R) is incorrect: During the freezing of water, heat is released (exothermic, H Since both H and S are negative, we can write G = -| H| + T| S| . For G to be negative, the magnitude of the enthalpy term must be greater than the magnitude of the entropy term, i.e., | H| > |T S| . The Reason incorrectly states that | H| Therefore

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