(e) VESPR rules

Question 1

What does VSEPR stand for?

Answer 1

Valency Shell Electron Pair Repulsion.

Question 2

What are these repulsion forces from?

Answer 2

Electrons.

Question 3

What are these repulsion forces responsible for?

Answer 3

The shape of polyatomic molecules.

Question 4

What are the rules?

Answer 4

1. Calculate the valency of the central atom
2. Add one for each bond the atom is making
3. If a molecule is an ion you must take the type of charge and number into account
4. Divide the resulting number by 2
5. Compare to the number of bonds.

Question 5

If an ion has a 1+ charge what would you do to the number?

Answer 5

Subtract one.

Question 6

Why do we divide the number by 2?

Answer 6

To calculate the number of electron pairs.

Question 7

Why do we compare to the number of bonds the atom is making?

Answer 7

To work out if there are any non-bonding electrons.