This attraction is known as hydrogen bonding, which occurs when a hydrogen atom that is covalently bonded to one electronegative atom (such as oxygen) is attracted to another electronegative atom in another molecule. In the case of water molecules, the hydrogen atoms have a partial positive charge and the oxygen atoms have a partial negative charge due to differences in electronegativity. This allows for the formation of hydrogen bonds between adjacent water molecules. The hydrogen bonding gives water its unique properties such as high boiling point and surface tension.