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MHT CET202120 Sep 2021Morning ShiftChemistryThermodynamics (C)Actual

Calculate difference between H and U for following reaction at 25^ C ? C ₂ H _ 6( ~g ) +3.50₂ 2 CO _ 2( ~g ) +3 H ₂ O _ ( l ) ( R =8.314 JK ⁻¹ ~mol ⁻¹ )

Options

  1. A-9.3 ~kJ
  2. B-3.1 ~kJ
  3. C-6.2 ~kJ
  4. D-16.10 ~kJ

Correct answer

C. -6.2 ~kJ

Step-by-step solution

aligned & H = U + n _ g RT & C ₂ H _ 6( ~g ) +3.5 O _ 2( ~g ) 2 CO _ 2( ~g ) +3 H ₂ O _ ( ) & n _ g =2-3.5-1=-2.5 & H - U = n _ g RT & =-2.5 8.314 298 & =-6193.93 ~J & =-6.19 ~kJ or -6.2 ~kJ aligned

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