Question

Assertion :The strength of haloacids increases in the order:
$HI<<HBr<<HCl<<HF$ Reason: Strength of acid HA depends only on the electronegativity difference between $H$ and $A$

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is D Both Assertion and Reason are incorrect

The correct order of acidic strength is: $HF<HCl<HBr<HI$.

While comparing elements in the same group of the periodic table, $H-A$ bond strength is a more important factor in determining acidity than its polar nature. As the size of $A$ increases down the group, $H-A$ bond strength decreases and so the acid strength increases.