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COMEDK202510 May 2025Evening ShiftChemistryThermodynamics (C)Actual

The Enthalpy of combustion of 1.0 mole of a reactive metal X at 27^ C and 1.0 bar pressure to form a solid oxide (XO) is -601.83 ~kJ / mol . The Internal energy change for this reaction is ______ kJ . ( R =8.314 J ~K ⁻¹ ~mol ⁻¹ )

Options

  1. A-614.30
  2. B701.33
  3. C754.58
  4. D-600.58

Correct answer

D. -600.58

Step-by-step solution

Reaction: X_ (s) + 1 2 O_ 2(g) XO_ (s) n_g = 0 - 1 2 = -0.5 mol U = H - n_g RT U = -601.83 - (-0.5 8.314 10⁻³ 300) U = -601.83 + 1.247 = -600.58 kJ

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