Final answer:
A pure sample of hydrogen chloride (HCl) exhibits dipole-dipole attractions as its primary intermolecular force, due to the different electronegativities of hydrogen and chlorine creating a partial positive and negative charge respectively.
Step-by-step explanation:
The intermolecular force present in a pure sample of hydrogen chloride (HCl) is dipole-dipole attractions. This is due to the polar nature of the HCl molecule, where chlorine (Cl) bears a partial negative charge and hydrogen (H) bears a partial positive charge. The positive end of one HCl molecule is attracted to the negative end of another, causing these molecules to experience electrostatic attraction towards each other. It is essential to understand that while hydrogen bonding is a special type of dipole-dipole interaction, it occurs when hydrogen is bonded to highly electronegative atoms like fluorine, oxygen, or nitrogen, which is not the case in HCl. Similarly, London dispersion forces are present in all molecules, but they are significantly weaker in small molecules like HCl compared to larger ones. Therefore, the primary intermolecular force in a pure sample of HCl is dipole-dipole attractions due to the dipole created by the electronegativity difference between H and Cl.