COMEDK · Chemistry · 6. Thermodynamics (C)
Enthalpy of formation of \(\mathrm{HF}\) and \(\mathrm{HCl}\) are \(-161 \mathrm{~kJ}\) and \(-92 \mathrm{~kJ}\) respectively. Which of the following statements is incorrect?
- A \(\mathrm{HCl}\) is more stable than \(\mathrm{HF}\).
- B \(\mathrm{HF}\) and \(\mathrm{HCl}\) are exothermic compounds.
- C The affinity of fluorine to hydrogen is greater than the affinity of chlorine to hydrogen.
- D \(\mathrm{HF}\) is more stable than \(\mathrm{HCl}\).
Answer & Solution
Correct Answer
(A) \(\mathrm{HCl}\) is more stable than \(\mathrm{HF}\).
Step-by-step Solution
Detailed explanation
As enthalpy of formation of \(\mathrm{HF}\) is more negative, than that of \(\mathrm{HCl}\) and \(\mathrm{HF}\) 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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