Question

what kind of intermolecular forces act between two ethylene (c₂h₄) molecules?
note: if there is more than one type of intermolecular force that acts, be sure to list them all, with a comma between the name of each force.

Explanation:

Ethylene ($\ce{C2H4}$) is a nonpolar molecule. The intermolecular forces acting between nonpolar molecules are London dispersion forces (also known as van der Waals forces or induced - dipole induced - dipole forces). Since ethylene has no permanent dipole (it is nonpolar) and no hydrogen atoms bonded to highly electronegative atoms (like N, O, F) for hydrogen bonding, only London dispersion forces are present.

Answer:

London dispersion forces