Relative order of acidity of HF, HCl, HBr and HI acids is

Correct answer: C. HI > HBr > HCl > HF

  • A. HCl > HBr > HI > HF
  • B. HF > HCl > HBr > HI
  • C. HI > HBr > HCl > HF
  • D. HF > HI > HCl > HBr

Explanation

The correct order of acidity for the halogen acids is HI > HBr > HCl > HF. This trend is due to the decreasing bond strength between the hydrogen and halogen atoms down the group. As you move down the group in the periodic table, the size of the halogen atoms increases, which leads to weaker H-X bonds and thus greater acidity. HF is an exception because of its strong hydrogen bonding, which makes it less acidic compared to the other halogen acids despite having a stronger H-F bond.

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