Explain why HCl is a gas and HF is a liquid.

HF has high boiling point than HCl because of the reason that in HF the strength of hydrogen bond is stronger than the strength of hydrogen bond in HCl.


This happens because the electronegativity of F atom is much more than that of Cl along with that F has a much smaller size. All these factors favour the formation of strong intermolecular hydrogen bonding with F atom. Due to the formation of strong and stable hydrogen bonding, high energy is required to break the H-F bond. So the boiling point of HF is more than HCl and due to which HF is a liquid and HCl is a gas.


Note – Both HCl and HF are gases at room temperature.


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