Question: why hcl is gas and hf is liquid?
Answer: 1 Answer. Due to greater electronegativity of F over Cl, F forms stronger H-bonds as compared to Cl. As a result, more energy is needed to break the H-bonds in HF than in HCl and hence the b.p. of HF is higher than that of HCl. Consequently, H-F is liquid while HCl is a gas at room temperature.