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COMEDK2013ChemistryThermodynamics (C)

Enthalpy of formation of HF and HCl are -161 ~kJ and -92 ~kJ respectively. Which of the following statements is incorrect?

Options

  1. AHCl is more stable than HF .
  2. BHF and HCl are exothermic compounds.
  3. CThe affinity of fluorine to hydrogen is greater than the affinity of chlorine to hydrogen.
  4. DHF is more stable than HCl .

Correct answer

A. HCl is more stable than HF .

Step-by-step solution

As enthalpy of formation of HF is more negative, than that of HCl and HF is more stable than HCl. The bond strength of hydrogen with halogen decrease down the group due to increases in size.

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