Final answer:
PH3 contains primarily London dispersion forces as it is a nonpolar molecule without significant permanent dipoles or the ability to form hydrogen bonds.
Step-by-step explanation:
The intermolecular forces that you would find in PH3 (phosphine) include primarily
London dispersion forces as the dominant type. Phosphine is a nonpolar molecule because the phosphorus-hydrogen bonds do not have a significant difference in electronegativity to create permanent dipoles. As a result, the molecule does not exhibit dipole-dipole interactions or hydrogen bonding.
London dispersion forces arise due to temporary fluctuations in electron distribution within molecules, leading to temporary dipole inductions on adjacent molecules. These forces are present in all molecules, regardless of whether they are polar or nonpolar.
Hydrogen bonding is a special type of dipole-dipole interaction that occurs when hydrogen is bonded to highly electronegative atoms like fluorine, oxygen, or nitrogen, which is not the case in PH3. Therefore, the correct intermolecular force present in PH3 is the London dispersion force.