C3 Structure and Bonding

Question 1

What is ionic bonding?

Answer 1

When an atom transfers electrons to another atom to form ions

Question 2

What type of elements form ionic bonds between them?

Answer 2

A metal and a non-metal

Question 3

What force holds ions together in ionic compounds?

Answer 3

Electrostatic forces

Question 4

What type of structure do ionic compounds form?

Answer 4

Giant lattices

Question 5

What is the charge on a Group 1 metal ion?

Answer 5

+1

Question 6

What is the charge on a Group 6 element’s ion?

Answer 6

-2

Question 7

How many electrons are in the outer shell of an ion?

Answer 7

Full outer shell (e.g. 8 or if the first shell 2)

Question 8

Draw the dot and cross diagram for a sodium ion.

Answer 8

Full outer shell of 8 electrons, square brackets, +1 charge outside the brackets.

Question 9

Do ionic compounds have high or low melting and boiling points?

Answer 9

High

Question 10

Why do ionic compounds have high melting and boiling points?

Answer 10

Strong ionic bonds (electrostatic forces) need a lot of energy to break them.

Question 11

When do ionic compounds conduct electricity?

Answer 11

Molten (melted) or in solution

Question 12

Why do ionic compounds conduct electricity when molten and in solution?

Answer 12

The ions are free to move

Question 13

What is covalent bonding?

Answer 13

Sharing of electrons

Question 14

What type of elements form covalent bonds between them?

Answer 14

Non-metals

Question 15

What type of structure do covalent compounds such as chlorine, water and methane form?

Answer 15

Simple covalent molecules

Question 16

Draw the dot and cross diagram for a chlorine molecule.

Answer 16

Two overlapping shells (circles). 2 electrons in the bond, 6 more in each shell.

Question 17

Do small molecules have high or low melting and boiling points?

Answer 17

Low

Question 18

Why do small molecules have low melting and boiling points?

Answer 18

Weak intermolecular forces (forces between the small molecules)

Question 19

Do larger molecules have higher or lower melting and boiling points?

Answer 19

Higher

Question 20

Do small covalent molecules conduct electricity?

Answer 20

No

Question 21

Why don’t small molecules conduct electricity?

Answer 21

No charged particles

Question 22

Why are polymers solid at room temperature?

Answer 22

Relatively strong intermolecular forces

Question 23

What is the bonding in a polymer?

Answer 23

Covalent

Question 24

Do giant covalent structures have high or low melting and boiling points?

Answer 24

High

Question 25

Why do giant covalent structures have high melting and boiling points?

Answer 25

It is the covalent bonds that are broken and they are strong so need a lot of energy to break them.

Question 26

Why is diamond hard?

Answer 26

Strong covalent bonds (4 per carbon)

Question 27

Can diamond conduct electricity? Explain why.

Answer 27

No. No free (delocalised) electrons.

Question 28

Why is graphite a solid at room temperature?

Answer 28

Strong covalent bonds (3 per carbon)

Question 29

Why can graphite be used as a lubricant?

Answer 29

Layers can slide over each other (weaker intermolecular forces between layers

Question 30

Can graphite conduct electricity? Explain why.

Answer 30

Yes. Free (delocalised) electrons can move and carry charge.

Question 31

What is graphene?

Answer 31

Single layer of graphite

Question 32

What properties make graphene useful?

Answer 32

Very good conductor of electricity, strong.

Question 33

What is metallic bonding?

Answer 33

Attraction between delocalised (free) electrons and positive ions

Question 34

Why can metals conduct electricity and thermal energy?

Answer 34

Delocalised (free) electrons can move and carry charge

Question 35

Why are alloys harder than pure metals?

Answer 35

Different sized metal atoms so the layers can’t slide over each other.