Hydrofluoric acid, H2F2 or HF is bad conductor of electricity. H−F bond is much stronger and hence, HF is a weak acid. It dissociates to a small extent. Hence, ions are not present for electrical conductivity. On the other hand, HCl, HBr and HI are strong acids and completely dissociate and provide ions for electrical conductivity. Hence, they are good conductors of electricity.