Wow, amazing question!! There are examples of bonds with very large atoms (for example, Br-C-Br) where the size of the Br atom causes the bond to expand larger than the predicted value as the big Br atoms try to move away from each other. This is usually not something we expect first year Chem students to be able to predict, though. But I LOVE that you’re thinking about this!
Great question! Yes, double bonds and triple bonds will also cause a similar decrease of the bond angle. Please make sure that you are not looking at a molecule with resonance structures, though, because those molecules will not experience the same type of bond angle distortion.
