Shapes Of Molecules

Question 1

Why do differing shapes form

Answer 1

Bonds repel each other equally- and electrons in bonds want to be as far apart as possible
- maximum separation + minimum repulsion

Question 2

How much more does a lone pair repel than a bonding pair

Answer 2

• generally each lone pair pushes the angle an extra 2.5•
• A structure just made of bonding pairs the angles will be equal

Question 3

Name of structure and angle with 2BP

Answer 3

Linear
180•

Question 4

Name of structure and angle with 3BP

Answer 4

Trigonal planar
120•

Question 5

Name of structure and angle with 4BP

Answer 5

Tetrahedral
109.5•

Question 6

Name of structure and angle with 5 BP

Answer 6

Trigonal Bipyramidial
120• between those on same plane
90• between those on different plane

Question 7

Name of structure and angle with 6 BP

Answer 7

Octahedral
90•

Question 8

Why do structures with no lone pairs have equal angles

Answer 8

Equal repulsion between bonding pairs = regular structures

Question 9

Name of structure and angle 3BP and 1 LP

Answer 9

Trigonal pyramidal
107•

Question 10

Name of structure and angle 2BP and 2LP

Answer 10

Bent / V-Shaped
104.5•

Question 11

Name of structure and angle 3BP and 2LP

Answer 11

Distorted T
87.5•

Question 12

Make of structure and angle 4BP and 1LP

Answer 12

Seesaw
87•
102•

Question 13

Name of structure and angle 5BP and 1LP

Answer 13

Square pyramidal
90• between 4 on same plan
81.9 between those on same plane and top BP

Question 14

Name of structure and angle 4BP
2LP

Answer 14

Square planar
90•
Lone pair on each side repel equally

Question 15

Why do Lone pairs repel more than Bonding pairs

Answer 15

Lone pairs are held closer to the nucleus of an atom = Repel more