Topic 2: Bonding, Structure and Properties of Matter

Question 1

Ions

Answer 1

Charged particles - single atoms or groups of atoms

Question 2

Giant ionic lattice (5)

Answer 2

Closely packed
regular lattice arrangement
with very strong electrostatic forces of attraction between oppositely charged ions
in all directions

Question 3

Properties of ionic compounds (4)

Answer 3

1) High melting and boiling points due to many strong bonds
2) Can’t conduct electricity when solid as there are no free ions
3) Dissolve easily in water
4) Can carry an electric current when molten or dissolved in water as the ions become free to move

Question 4

Covalent bonding (2)

Answer 4

1) Non-metal atoms share pairs of electrons in their outer shells
2) Positively-charged nuclei of the atoms are attracted to the shared pair of electrons by very strong electrostatic force of attraction

Question 5

Properties of simple molecular substances (3)

Answer 5

1) Low melting and boiling points due to feeble intermolecular forces (despite very strong covalent bonds)
2) Gases or liquids at room temperature
3) Can’t conduct electricity as there are no free electrons

Question 6

Polymers

Answer 6

Long chains of repeating units joined by covalent bonds

Question 7

Why are polymers solid at room temperature when simple molecular substances are fluid?

Answer 7

The intermolecular forces are larger than in simple molecules so more energy is needed to break them

Question 8

Giant covalent structures

Answer 8

Structures where all the atoms are bonded to each other by strong covalent bonds

Question 9

Properties of giant covalent structures (2)

Answer 9

1) Very high melting and boiling points due to many strong covalent bonds
2) Can’t conduct electricity as there are no charged particles (except graphite)

Question 10

Graphite (2)

Answer 10

1) An allotrope of carbon where each carbon atom forms three covalent bonds
2) Structured in layers of carbon atoms arranged as hexagons

Question 11

Properties of graphite (3)

Answer 11

1) Soft and slippery (used for lubricants) as there aren’t any covalent bonds between layers
2) High melting and boiling point due to covalent bonds in layers
3) Can conduct electricity as each carbon atom has one delocalised electron because only three out of carbon’s four outer electrons are used in bonds

Question 12

Properties of graphene (3)

Answer 12

1) Incredibly light (one-cell thick)
2) Very strong so added to composite materials
3) Can conduct electricity so used in electronics

Question 13

Fullerenes

Answer 13

Molecules of carbon shaped like closed tubes or hollow balls made up of carbon atoms arranged in pent/hex/heptagons

Question 14

Properties of fullerenes (2)

Answer 14

1) Can cage other molecules

2) Huge surface area

Question 15

Uses of fullerenes (3)

Answer 15

1) By caging molecules it can deliver drugs into the body
2) Huge surface area makes them good industrial catalysts
3) Good lubricants

Question 16

Properties of nanotubes (3)

Answer 16

1) Thin as the ratio between length and diameter is huge
2 High tensile strength
3 Can conduct electricity

Question 17

Uses of nanotubes (2)

Answer 17

1) Used in nanotechnology as they are very thin

2) Used to strengthen materials without adding weight

Question 18

Metallic bonding

Answer 18

The sea of delocalised negative electrons from the
metal atoms have strong electrostatic forces of attraction with the positive metal ions holding the atoms together in a regular structure

Question 19

Malleable

Answer 19

Can be bent, hammered, rolled into flat sheets

Question 20

Alloys

Answer 20

Harder than pure metals as they are a mixture of two or more metals which means the different sized atoms of the different metals disrupt the layers of metal atoms, making it harder for them to slide over each other