Molecular geometry

Question 1

What is the electron pair repulsion theory?

Answer 1

Electron pairs repel one another and cause the molecule to adopt a shape which will cause for the least amount of repulsion - want to be as far apart from each other as possible

Question 2

How do lone pairs influence the shape of a molecule?

Answer 2

Add extra repulsion (reduces angle by 2.5 degrees)

Question 3

2 bonding pairs, 0 lone pairs - what is the shape and angle?

Answer 3

Linear, 180 degrees
Y - X - Y

Question 4

3 bonding pairs, 0 lone pairs - what is the shape and angle?

Answer 4

Trigonal planar, 120 degrees

    Y
    | Y — X — Y

Question 5

4 bonding pairs, 0 lone pairs - what is the shape and angle?

Answer 5

Tetrahedral, 109.5 degrees

Question 6

3 bonding pairs, 1 lone pair - what is the shape and angle?

Answer 6

Trigonal pyramid, 107 degrees

Question 7

2 bonding pairs, 2 lone pairs - what is the shape and angle?

Answer 7

Non-linear, 104.5 degrees

Question 8

6 bonding pairs, 0 lone pairs - what is the shape and angle?

Answer 8

Octahedral, 90 degrees