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MHT CET20243 May 2024Morning ShiftChemistryThermodynamics (C)Actual

If bond formation energy of H - H bond is -433 ~kJ ~mol ⁻¹ find the bond dissociation energy for 0.5 mole H _ 2( ~g ) .

Options

  1. A108.0 kJ
  2. B216.5 kJ
  3. C433.0 kJ
  4. D324.5 kJ

Correct answer

B. 216.5 kJ

Step-by-step solution

For the given reaction, H _ 2( ~g ) 2 H _ ( g ) , _ r H ^ =433 ~kJ ~mol ⁻¹ (Bond dissociation energy for 1 mole of H _ 2( ~g ) =- H - H bond formation energy) Bond dissociation energy for 0.5 moles of H ₂=0.5 433 ~kJ =216.5 ~kJ

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