The structure of hydrogen chloride (HCl) consists of hydrogen (H) bonded to chlorine (Cl) through a single covalent bond. It is a linear molecule with a bond angle of 180 degrees. The electronegativity of hydrogen is 2.2, and that of carbon is 3.16. Since chlorine is more electronegative than hydrogen, it will attract the shared electron pair. Therefore, the electronegativity difference results in a partial positive charge on hydrogen and a partial negative charge on chlorine, making HCl a polar molecule.