True. Hydrogen fluoride (HF) is indeed a polar molecule due to its molecular structure and the electronegativity difference between hydrogen and fluorine.
In HF, the fluorine atom is highly electronegative, meaning it has a strong tendency to attract electrons towards itself. This creates a partial negative charge (δ-) near the fluorine atom and a partial positive charge (δ+) near the hydrogen atom. The molecule has an asymmetrical distribution of charge, which is a characteristic of polar molecules.
Additionally, the bond between hydrogen and fluorine is predominantly covalent, but the significant difference in electronegativity results in a dipole moment, reinforcing the polarity of the molecule. Overall, the polarization in HF not only affects its physical properties, such as its high boiling point for a small molecule but also its behavior in chemical reactions. Therefore, it is correct to state that hydrogen fluoride is a polar molecule.