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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 ice at -10^ C is a spontaneous process even though the entropy of the system decreases. Reason (R): For this exothermic process, the heat released to the surroundings increases the entropy of the surroundings sufficiently so that the total entropy change is positive.

Options

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

B. Both (A) and (R) are correct and (R) is the correct explanation of (A)

Step-by-step solution

Assertion (A) is correct. Freezing of water to ice is a phase transition from liquid to solid, which results in a more ordered state, meaning the entropy of the system decreases ( S_ sys Reason (R) is also correct and explains (A). According to the Second Law of Thermodynamics, a process is spontaneous if the total entropy change of the universe is positive ( S_ total = S_ sys + S_ surr > 0 ). Freezing is an exothermic process ( H_ sys 0 . Therefore, both (A) and (R) are correct and (R) is the correct explanation o

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