No lone pairs shapes and angles

how do pairs of electrons in the outer shell arrange themselves

as far apart as possible to minimise repulsion

what does planar mean

flat (all atoms in same plane)

which pairs of electrons have the greatest repulsion

1. lone pair - lone pair
2. lone pair - bond pair
3. bond pair - bond pair

How does a lone pair affect bond shape

It affects bond angle by 2.5º

what does a wedge tell us

coming out of the page

what does a dotted line tell us

behind plane of page

what does a solid line tell us

on plane of page

what is shape of a molecule determined by

the electron pairs surrounding the CENTRAL atom (as electron pairs repel other pairs)

how do we treat a lone pair

as another bond (e.g if there are 3 atoms and one lone pair then has the tetrahedral shape)

what if the lone pair has dative covalent

then the bond angle is that of a normal molecule, despite being a lone pair (no extra repulsion)

what is a covalent bond

a pair of electrons

2 bonding pairs 0 lone pairs

linear, 180°

3 bonding pairs

trigonal planar, 120

4 bonding pairs

Tetrahedral 109.5

5 bonding pairs

trigonal bipyramidal, 90 120

6 bonding pairs

Octahedral 90

explain why x has bond angle x

there are x bonding pairs of electrons, therefore they repel equally and spread out evenly as far apart as possible.

when is it obvious there is a dative covalent bond

when something bonds to a H+ (pair of electrons donated to H+)

type of bond how it is formed question

this is always a dative/coordinate bond question
1. coordinate bond
2. the H+ gains 2e- from other atom/molecule