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AP EAMCET2009ChemistryThermodynamics (C)

Given that H_f( H )=218 ~kJ / mol , express the H - H bond energy in kcal / mol .

Options

  1. A52.15
  2. B911
  3. C104
  4. D52153

Correct answer

C. 104

Step-by-step solution

Given : H_f( H )=218 ~kJ / mol ie, 1 2 H ₂ H ; H=218 ~kJ / mol aligned & or H ₂ 2 H ; H=436 ~kJ / mol & = 436 4.18 =104.3 kcal / mol & aligned Thus, 104.3 kcal / mol energy is absorbed for breaking one mole of H - H bonds. Hence, H - H bond energy is 104.3 kcal / mol .

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