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AP EAMCET202120 Aug 2021Morning ShiftChemistryThermodynamics (C)Actual

For the reaction H 2 O ( l ) ⟶ H 2 O ( g ) at T = 100 ° C and P = 1 atm , choose the correct option:

Options

  1. AΔS system   > 0 & ΔS surroundings   > 0
  2. BΔS system   > 0   &  ΔS surroundings   < 0
  3. CΔS system   < 0   &  ΔS surroundings   > 0
  4. DΔS system   < 0   &  ΔS surroundings   < 0

Correct answer

B. ΔS system   > 0   &  ΔS surroundings   < 0

Step-by-step solution

The given reaction is: H 2 O l   → H 2 O g It is the equilibrium reaction We know that at equilibrium position ∆ S universe   =   0 i Also, the relation between entropies of system and surrounding is ∆ S universe   = ∆ S system + ∆ S surrounding 0   = ∆ S system + ∆ S surrounding ∆ S system = - ∆ S surrounding So, from the given option ΔS system   > 0   &  ΔS surroundings   < 0

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