5. Bonding

Question 1

Draw and name the shape.
Find the bond angle.
2 e- pairs, no LPs

Answer 1

Question 2

Draw and name the shape.
Find the bond angle.
3 e- pairs, no LPs

Answer 2

Question 3

Draw and name the shape.
Find the bond angle.
3 e- pairs, 1 LP

Answer 3

Question 4

Draw and name the shape.
Find the bond angle.
4 e- pairs, no LPs

Answer 4

Question 5

Draw and name the shape.
Find the bond angle.
4 e- pairs, 1 LP

Answer 5

Question 6

Draw and name the shape.
Find the bond angle.
4 e- pairs, 2 LPs

Answer 6

Question 7

Draw and name the shape.
Find the bond angle.
5 e- pairs, no LPs

Answer 7

Question 8

Draw and name the shape.
Find the bond angle.
5 e- pairs, 1 LP

Answer 8

89⁰, 119⁰

Question 9

Draw and name the shape.
Find the bond angle.
5 e- pairs, 2 LPs

Answer 9

Question 10

Draw and name the shape.
Find the bond angle.
5 e- pairs, 3 LPs

Answer 10

Question 11

Draw and name the shape.
Find the bond angle.
6 e- pairs, no LPs

Answer 11

Question 12

Draw and name the shape.
Find the bond angle.
6 e- pairs, 1 LP

Answer 12

Question 13

Draw and name the shape.
Find the bond angle.
6 e- pairs, 2 LPs

Answer 13

Question 14

Describe Metallic Bonding:

Answer 14

• between 2 or more metals
• giant metallic lattice
• metallic → strong electrostatic attraction between positive metal ions and delocalised e-

Question 15

Describe Ionic Bonding:

Answer 15

• between metal and non metal
• giant ionic lattice
• ionic → strong electrostatic attraction between oppositely charged ions

Question 16

Describe Covalent (Macromolecular) Bonding:

Answer 16

• uses either Carbon or Silicon
• macromolecular structure
• covalent bonds between atoms

Question 17

Examples of Macromolecular Structures:

Answer 17

Diamond
- each C atom has 4 covalent bonds
- tetrahedral shape
- very high mpt, very strong
- non-conductor = no free (delocalised) e-

Graphite
- layered
- each 3 atom has 3 covalent bonds
- each C atoms has delocalised e-
- layers held together by weak intermolecular forces
- soft layers can slide over each other
- conductor = has delocalised e-
- high mpt

Question 18

Describe Covalent (Simple Molecular) Bonding

Answer 18

• Hydrogen bonding: H,F, H-N, H-O
• P.D.D: polar molecule
• I.D.D: non-polar molecular
• structure: simple molecular
• bonding: intermolecular (Hydrogen, P.D.D, I.D.D) forces between molecules

Question 19

Coordinate Bond Definition

Answer 19

a shared pair of e- which have both come from the same atom

represented by an arrow coming from the atom that is sharing its e-

is exactly like a normal covalent bond

Question 20

Rank the stength of repulsions between e- pairs

Answer 20

• LP to LP > LP to BP > BP to BP

Question 21

Electronegativity Definition:

Answer 21

the power of an atom to attract a pair of e- in a covalent bond

Question 22

Factors Affecting Electronegativity

Answer 22

• shielding
• nuclear charge (proton number)
• (atomic radius)

Question 23

How do you work out if a molecule is polar?

Answer 23

assymetrical
- all atoms around the central atoom are the same and there is a LP
OR
- 1 atom around the central atom is different and [no LPs or >1 LP]

Question 24

How do you work out if the molecule is non-polar?

Answer 24

• symmetrical
• all atoms aroumd central atom are the same
• no LPs

Question 25

Name and decribe the type of bonding between only metal ions:

Answer 25

- Giant Metallic Lattice - Metallic Bonding - electrostatic attraction between +ve metal ion and delocalised e-

Question 26

Name and describe the type of bonding between metal and non-metal ions:

Answer 26

- Giant ionic lattice - electrostatic attraction between oppositely charged ions

Question 27

Name and decribe the type of bonding between non-metals if the substance contains C,Si, or is SiO2:

Answer 27

- Macromolecular - Covalent bonding between atoms

Question 28

Name and describe the type of bonding between non-metals if the molecule contains bond between, H-F, H-N OR H-O:

Answer 28

- Simple Molecular - IMF - Hydrogen bonding between molecules

Question 29

Name and describe the type of bonding between non-metals if the molecule is polar (assymetrical):

Answer 29

- Simple Molecular - IMF - P.D.D forces between molecules

Question 30

Name and decribe the type of bonding between non-metals if the molecules is non-polar:

Answer 30

- Simple-Molecular - IMF - I.D.D forces between molecules (more e- makes these forces stronger)

Question 31

When does H bonding occur?

Answer 31

- strongest IMF - between a H atoms bonded to a [O/F/N] atom and a LP on a [O/F/N] atom

Question 32

How does H bonding occur?

Answer 32

- large difference in electronegativity between N/O/F and H - creates a dipole on the H-F/H-N/H-O bond - LP on the N/O/F atom on 1 molecule strongly attracts a 𝝳+ H atom on a different molecule

Question 33

When does P.D.D occur?

Answer 33

- generally weaker than H bonding - occurs between polar (assymetrical) molecules

Question 34

How does the P.D.D arise?

Answer 34

- difference in electronegativity leads to bond polarity - dipoles don't cancel and therefore molecule has an overall permanent dipole - attraction between 𝜹+ on one molecule and 𝜹- on another molecule

Question 35

Draw P.D.D forces between 2 SbCl3 molecules:

Answer 35

Question 36

When does I.D.D occur?

Answer 36

- generally the weakest force, but can be stronger than both P.D.D and hydrogen bonding if the molecule is large - occurs between all molecules (as well as atoms of nobles gases) - most important for non-polar molecules (as they don’t have any other IMFs)

Question 37

When does it occur?

Answer 37

RUTID - R: random Movement of e- in 1 molecules leads to … - U: uneven distribution of e-, creating a … - T: temporary dipole in 1 molecules (atom). This … - I: induces a dipole in the neighbouring molecule (atom). - D: dipole attract

Question 38

How to draw I.D.D?

Answer 38

Question 39

Importance of H bonding:

Answer 39

1) ice: ice less dense than water because the H bonds in ice hold the molecules further apart 2) proteins: proteins are held in their specific complex 3D shape by H bonds (secondary/tertiary structure) 3) DNA: 2 strands are held together by H bonds. strong enough to hold strands together but weak enough to allow strands to separate for DNA replication