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JEE Main202117 Mar 2021Evening ShiftChemistryThermodynamics (C)Actual

During which of the following processes, does entropy decrease ? (A) Freezing of water to ice at 0 ° C (B) Freezing of water to ice at - 10 ° C (C) N 2 ( g ) + 3 H 2 ( g ) → 2 NH 3 ( g ) (D) Adsorption of CO ( g ) and lead surface (E) Dissolution of NaCl in water

Options

  1. A(A), (B),(C) and (D) only
  2. B(B) and (C) only
  3. C(A) and (E) only
  4. D(A), (C) and (E) only

Correct answer

A. (A), (B),(C) and (D) only

Step-by-step solution

(A) Water ⟶ 0 ° C ice; Δ S = - ve (B) Water ⟶ - 10 ° C ice; Δ S = - ve (C) N 2 (   g ) + 3 H 2 (   g ) → 2 NH 3 (   g ) ; Δ S = - ve (D) Adsorption; Δ S = - ve (E) NaCl ( s ) → Na + ( aq ) + Cl - ( aq ) ; Δ S = + ve

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