Sapling #3

[IreneGi2I]

For number 3 of Sapling homework, the below lewis structure of a molecule is given. And the question is asking what the smallest bond angle would be.

I thought this structure is similar to H2O, which is bent shape, but the solution says that it is actually a linear shape (and smallest bond angle is 180 degree). Can someone explain why that is?

[Ivan Chen 2H]

That would be correct if the molecule had 2 lone pairs. However, since it has three lone pairs, the lone pairs occupy the equatorial positions and forces the "x" atoms into the axial positions. This is what makes them linear.

[Katherine_Douglas_1F]

The bonded pairs are on the axil and the lone pairs are on the equatorial plane. Because they all cancel out, the molecule is nonpolar and also linear.

[Nick Pascua 2L]

Hi!

Ivan is right. Adding another lone pair where there are 2 bonds and 2 lone pairs would cause a bent structure to be linear again. Just remember that adding 1 or 2 lone pairs to a linear structure will cause it to bend, but adding a 3rd will even out the push in electron densities. I hope that helps!

[Algernon Jackson 2l]

It is linear because the bonded pairs are on the axil and the lone pairs are on the equatorial plane.