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MHT CET202012 Oct 2020Morning ShiftChemistryThermodynamics (C)Actual

For the following reaction Fe ₂ O _ 3( ~s ) +3 CO _ ( g ) 2 Fe _ ( s ) +3 CO _ 2( ~g ) H ^ =-29 8 ~kJ and S ^ =15 JK ⁻¹ . What is the value of S _ (total) at 298 ~K ?

Options

  1. A29.8 J
  2. B100 0 ~J
  3. C298 0 ~J
  4. D115 0 ~J

Correct answer

D. 115 0 ~J

Step-by-step solution

Since the reaction is exothermic, system loses heat to surrounding. Hence the entropy of the surrounding increases. aligned H _ surr &=+29.8 ~kJ =29800 ~J S _ sur &= H _ sur T = 29800 298 =100 JK ⁻¹ S _ Total &= S _ sys + S _ surr =15+100=115 JK ⁻¹ aligned

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