C2 Bonding, structure and the properties of matter

Question 1

What are the three types of chemical bonds?

Answer 1

The three types of chemical bonds are ionic bonds, covalent bonds and metallic bonds.

Question 2

Where do ionic bonds form?

Answer 2

Ionic bonds form between metals and non-metals.

Question 3

Where do covalent bonds form?

Answer 3

Covalent bonds form between non-metal atoms.

Question 4

Where do metallic bonds form?

Answer 4

Metallic bonds form in mettalic elements and alloys.

Question 5

What are the particles involved with ionic bonding?

Answer 5

For ionic bonding the particles are oppositely charged ions.

Question 6

What are the particles involved with covalent bonding?

Answer 6

For covalent bonding the particles are atoms which share pairs of electrons.

Question 7

What are the particles involved with metallic bonding?

Answer 7

For metallic bonding the particles are atoms which share delocalised electrons.

Question 8

Ionic bonding involves the transfer of what?

Answer 8

Ionic Bonding involves the transfer of electrons.

Question 9

Do metals lose or gain electrons?

Answer 9

Metals lose electrons.

Question 10

Do non metals lose or gain electrons?

Answer 10

Non metals gain electrons.

Question 11

What is the charge of a metal ion?

Answer 11

The charge of a metal ion is positive.

Question 12

What is the charge of a non-metal ion?

Answer 12

The charge of a non-metal ion is negative.

Question 13

Draw a dot and cross diagram showing the formation of NaCl. Include electronic configurations.

Answer 13

Question 14

What is an ionic compound and how are ions held together?

Answer 14

An ionic compound is a giant structure of ions. Ionic compounds are held together by strong electrostatic forces of attraction between oppositely charged ions.

Question 15

What is a giant ionic lattice?

Answer 15

A giant ionic lattice is made up of oppositely charged ions held togther by electrostaic forces acting in all directions. This is called ionic bonding.

Question 16

What does the picture of the giant ionic lattice of sodium chloride look like?

Answer 16

Question 17

What are covalent bonds?

Answer 17

When atoms share pairs of electrons, they form covalent bonds. These bonds between atoms are strong.

Question 18

What different diagrams can covalent structures be represented by?

Answer 18

Question 19

Draw dot and cross diagrams for the molecules of hydrogen, chlorine, oxygen, nitrogen, hydrogen chloride, water, ammonia and methane.

Answer 19

Question 20

What is metallic bonding?

Answer 20

Metals consist of giant structures of positive metal cations arranged in a regular pattern. The cations are surrounded by delocalised electrons. The attractions between of delocalised electrons and positive cations gives rise to strong metallic bonds.

Question 21

What does metallic bonding look like?

Answer 21

Question 22

What are the three states of matter?

Answer 22

The three states of matter are solid, liquid and gas.

Question 23

What determines the melting and boiling point of substances?

Answer 23

The melting and boiling points of substances are determined by the forces between the particles. This depends upon the structure and bonding within the substance.

Question 24

List the state symbols used in chemical equations.

Answer 24

• Solid (s)
• Liquid (l)
• Gas (g)
• Aquesous (aq)

Aqueaous measn the substance is dissolved in water.

Question 25

Why do ionic compounds have high melting points?

Answer 25

Ionic compounds have high melting points and high boiling points because of the large amounts of energy needed to break the many strong bonds.

Question 26

Why do ionic compunds conduct electricity when molten or dissolved, but not when solid?

Answer 26

When melted or dissolved in water, ionic compounds conduct electricity because the ions are free to move and so charge can flow.

Question 27

Describe some of the physical properties of small molecules.

Answer 27

Small molecules are usually gases or
liquids that have relatively low melting points and boiling points.

Question 28

Describe the the strength of the intermolecular forces between small molecules.

Answer 28

Small molecules have only weak forces between the molecules (intermolecular forces). It is these intermolecular forces that are overcome, not the covalent bonds, when the substance melts or
boils.

Question 29

What is the pattern in melting and boiling points as molecule size gets bigger?

Answer 29

The intermolecular forces increase with the size of the molecules, so larger molecules have higher melting and boiling points.

Question 30

Do small covalent molecules conduct electricity?

Answer 30

No, small covalent molecules do not conduct electricity as there is no overall charge or spare ions or electrons to carry a charge.

Question 31

Polymers have very strong covalent bonds between atoms, true or false?

Answer 31

TRUE! Atoms in polymers are held in palce by strong covalent bonds.

Question 32

Describe what a monomer looks like.

Answer 32

A monomer is an unsaturated compound with a double bond.

Question 33

What does a polymer look like?

Answer 33

Question 34

Explain why polymer molecules are solids at room temperature.

Answer 34

Polymer molecules are solid at room temperature because they have relatively strong intermolecular forces between polymer chains.

Question 35

Giant covalent structures are solids with high melting points. Expalin why.

Answer 35

Giant covalent compounds are solids with high metling points because the atoms are held together by strong covalent bonds that require large amounts of energy to break them.

Question 36

Give three examples of giant covalent structures.

Answer 36

Three examples of giant covalent structures are diamond, graphite and silicon dioxide.

Question 37

Metals have stong metallic bonding which makes them have high melting and boiling points. Explain why.

Answer 37

Strong metallic bonds are held together by strong forces of attraction between positive metal cations and delocalised electrons. They need lots of energy to be broken.

Question 38

Why do metals conduct electricity.

Answer 38

Metals conduct electricity because delocalised electrons are free to carry the electrical charge.

Question 39

Pure metals can be bent or drawn into wires. What are the names given to these properties?

Answer 39

Metals that can be bent are called malleable. Metals that can be drawn into wires are called ductile.

Question 40

How are pure metals made harder?

Answer 40

Pure metals are made harder by combining them with other metals to make alloys.

Question 41

Describe the bonding in diamond and some of its properties.

Answer 41

In diamond, each carbon atom forms four covalent bonds with other carbon atoms in a giant covalent structure, so diamond is very hard, has a very high melting point and does not conduct electricity.

Question 42

Describe the bonding in graphite.

Answer 42

In graphite, each carbon atom forms three covalent bonds with three other carbon atoms, forming layers of hexagonal rings which have no covalent bonds between the layers. In graphite, one electron from each carbon atom is delocalised.

Question 43

Describe the properties of graphite in relation to its structure.

Answer 43

Graphite is soft and slippery becuase of the weak intermolecular forces between layers. The delocalised electrons allow graphite to carry an electrical charge so it conducts electricity.

Question 44

Describe the structure of graphene and give one use of this material.

Answer 44

Graphene is made up of a single layer of graphite. It can be used in electrical circuits.

Question 45

Describe fullerenes and give a named example.

Answer 45

Fullerenes are molecules of carbon atoms with hollow shapes. The structure of fullerenes is based on hexagonal rings of carbon atoms but they may also contain rings with five or seven carbon atoms. The first fullerene to be discovered was buckminsterfullerene (C60) which has a spherical shape.

Question 46

What are carbon nanotubes and why are they useful?

Answer 46

Carbon nanotubes are cylindrical fullerenes with very high length to diameter ratios. Their properties make them useful for nanotechnology, electronics and materials.

Question 47

What do the allotropes of carbon look like?

Answer 47