### Ch8 Sample Problem #21

```PROBLEM: Draw a Lewis structure for each of the following molecules or ions.
Describe the electron-pair geometry and molecular geometry around the central atom.
(a) ClF2–
(b) ClF3
(c) ClF4–
(d) ClF5
Step 1: Draw the Lewis structure
(a) ClF2–
(b) ClF3
_
_
_
/\
–
|F – Cl – F|
|F|
_
|
_
|F – Cl – F|
\/
(c) ClF4–
(d) ClF5
_
_
_
–
|F|
|Cl| |Cl|
_
|/
_ \ / _
|F – Cl – F|
|F – Cl – F|
/|
/ \
|F|
|F|
Step 2: The electron geometry is determined by the number of electron domains surrounding the central
atom. The molecular geometry is determined by the number of shared and unshared pairs around the
central atom
(a) ClF2–
(b) ClF3
(c) ClF4–
(d) ClF5
Electron geometry
5 e– domains
trigonal bipyramidal
5 e– domains
trigonal bipyramidal
6 e– domains
octahedral
6 e– domains
octahedral
Molecular Geometry
Two shared pairs
Three unshared pairs
Linear
Three shared pairs
Two unshared pairs
T-shaped
Four shared pairs
Two unshared pairs
Square planer
Five shared pairs
One unshared pairs
Square pyramidal
```