Bond angles

[Gurvardaan Bal1L]

If there are multiple regions of electron density (Say 5) and you have one lone pair of electrons, the shape would then be a seesaw. How do you know what the angles are for the bonds in the molecule? I know the lone pair would have some effect on the angle of the bond but I'm not really sure how to determine the effect of the electrons.

[Cynthia Tsang]

Lone pairs provide more repulsion than other atoms with electrons attached. Therefore the angles between the lone pairs and the atoms will be bigger than expected for the shape, and the angles between the atoms will be smaller because the lone pair pushes them closer together.

[Matthew 1C]

And while you know that the angles will be either slightly larger or slightly smaller, I think the only way to find out the exact angle is to look it up

[Ramya Lakkaraju 1B]

We are only expected to know the general bond angles (such as less than 120, etc) since the exact bond angles can only be determined from experimental observation.