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Manipal MET2016ChemistryThermodynamics (C)

Enthalpy of formation of HF and HCl are -161 kJ and -92 kJ , respectively. Select the incorrect statement on the basis of the above fact.

Options

  1. AHF is more stable than HCl
  2. BHCl is more stable than HF
  3. CAffinity of fluorine to hydrogen is greater than affinity of chlorine to hydrogen
  4. DHF and HCl are exothermic compound

Correct answer

B. HCl is more stable than HF

Step-by-step solution

HF is more stable than HCl because more energy is produced in the formation of HF. It means HF has less energy than HCl and hence is more stable. So, we need more energy to break H-F bond. Hence, HF is more stable.

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