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NEETChemistryThermodynamics (C)

For oxidation of iron, 4Fe(s) + 3O 2 (g) → 2Fe 2 O 3 (s) entropy change is –549.4 JK –1 mol –1 at 298 K. Inspite of negative entropy change of this reaction, why is the reaction spontaneous? (∆ r H for this reaction is –1648 × 10 3 Jmol –1 )

Options

  1. ABecause total entropy (△S system​ +△S surrounding ) is positive
  2. BBecause total entropy (△S system​ +△S surrounding ) is negative
  3. CBecause total entropy (△S system​ +△S surrounding ) is constant
  4. DBecause total entropy (△S system​ +△S surrounding ) is zero

Correct answer

A. Because total entropy (△S system​ +△S surrounding ) is positive

Step-by-step solution

Correct Option is : (A) Because total entropy (△S system​ +△S surrounding ) is positive

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