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AP EAMCET202120 Aug 2021Evening ShiftChemistryThermodynamics (C)Actual

Find the approximate value of ( ΔH - ΔU ) in J · mol - 1 , for the formation of CO from its elements at 298 K . R = 8 . 314 J · K - 1 mol - 1

Options

  1. A- 1238
  2. B1238
  3. C2477
  4. D- 2477

Correct answer

B. 1238

Step-by-step solution

C + 1 2 O 2 → CO Δn g = Number   of   gaseous   products - number   of   gaseous   reactants Δn g = 1 - 1 - 1 2 = - 1 2 R = 8 . 314   J · K - 1   mol - 1 Temperature T = 298 K ΔH = ΔU - Δn g RT ΔH - ΔU = - Δn g RT ΔH - ΔU = 1 2 × 8 . 314 × 298 = 1238 Hence, the value of ΔH - ΔU is equal to the 1238 J · mol - 1 .

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