If a molecule has polar bonds, does it also have Dipole-Dipole IMF’s? Explain.

Question

If a molecule has polar bonds, does it also have Dipole-Dipole IMF’s? Explain.

(This is my explanation) This depends on whether the molecule is polar or nonpolar because the polarity of a molecule is not only determined by the presence of polar bonds, but also by the shape of the molecule. Dipole-dipole forces occur when the positive part of a polar molecule is attracted to the negative partial charge of another polar molecule. In a nonpolar molecule, there may still be polar bonds, but the dipoles cancel each other out. Hence, dipole-dipole forces only occur in polar molecules.
*******Would you mind checking it?

Answer 1

I think the first part of your explanation is OK. I think, perhaps, your second part needs a little work if I understood it correctly. From the way I read the second part here are two examples I thought of.

H2, N2, O2 are non-polar molecules and the bonds are non-polar so I'm having trouble understanding what dipoles cancel out. There aren't any dipoles.
Another example is CH4. The 4 C-H bonds are polar (slightly) but the shape is tetrahedral which makes it symmetrical; thus the molecule is non-polar. Again, what dipoles cancel out. There aren't any dipoles or have I missed something?

Answer 2

Your explanation is correct! You have accurately explained that the presence of polar bonds does not guarantee the presence of dipole-dipole intermolecular forces (IMFs) in a molecule. The shape of the molecule is also an important factor in determining its overall polarity. In a nonpolar molecule, the individual polar bonds may exist, but if they are symmetrically arranged in such a way that the dipoles cancel each other out, then the molecule as a whole is nonpolar. Only in polar molecules, where there is an asymmetric distribution of electron density, will dipole-dipole IMFs occur. Well done!