3. Structure and Bonding Flashcards
1
Q
1. What is ionic bonding?
A
- When an atom transfers electrons to another atom to form ions
2
Q
- What type of elements form ionic bonds between them?
A
- A metal and a non-metal
3
Q
- What force holds ions together in ionic compounds?
A
- Electrostatic forces
4
Q
- What type of structure do ionic compounds form?
A
- Giant lattices
5
Q
- What is the charge on a Group 1 metal ion?
A
- +1
6
Q
- What is the charge on a Group 6 element’s ion?
A
- -2
7
Q
- How many electrons are in the outer shell of an ion?
A
7.Full outer shell (e.g. 8 or if the first shell 2)
8
Q
- Do ionic compounds have high or low melting and boiling points?
A
- High
9
Q
- Why?
A
- Strong ionic bonds need a lot of energy to break them.
10
Q
- When do ionic compounds conduct electricity?
A
- Molten (melted) or in solution
11
Q
- Why?
A
- The ions are free to move
12
Q
- What is covalent bonding?
A
13.Sharing of electrons
13
Q
- What type of elements form covalent bonds between them?
A
- Non-metals
14
Q
- What type of structure do covalent compounds such as chlorine, water and methane form?
A
- Simple covalent molecules
15
Q
- Do small molecules have high or low melting and boiling points?
A
- Low
16
Q
- Why do small molecules have low boiling point?
A
- Weak intermolecular forces (forces between the small molecules)
17
Q
- Do larger molecules have higher or lower melting and boiling points?
A
- Higher
18
Q
- Do small covalent molecules conduct electricity?
A
- No
19
Q
- Why don’t small molecules conduct electricity?
A
- No charged particles
20
Q
- Why are polymers solid at room temperature?
A
- Relatively strong intermolecular forces
21
Q
- What is the bonding in a polymer?
A
- Covalent
22
Q
- Do giant covalent structures have high or low melting and boiling points?
A
- High
23
Q
- Why do giant covalent have high melting points?
A
- It is the covalent bonds that are broken and they are strong so need a lot of energy to break them.
24
Q
- Why is diamond hard?
A
- Strong covalent bonds (4 per carbon)
25
Q
- Can diamond conduct electricity? Explain why.
A
- No. No free (delocalised) electrons.
26
Q
- Why is graphite a hard, solid at room temperature?
A
- Strong covalent bonds (3 per carbon)
27
Q
- Why can graphite be used as a lubricant?
A
- Layers can slide over each other (weaker intermolecular forces between layers
28
Q
- Can graphite conduct electricity? Explain why.
A
- Yes. Free (delocalised) electrons can move and carry charge.
29
Q
- What is graphene?
A
- Single layer of graphite
30
Q
- What properties make it useful?
A
- Very good conductor of electricity, strong.
31
Q
- What is metallic bonding?
A
- Attraction between delocalised (free) electrons and positive ions
32
Q
- Why can metals conduct electricity and thermal energy?
A
- Delocalised (free) electrons can move and carry charge
33
Q
- Why are alloys harder than pure metals?
A
- Different sized metal atoms so the layers can’t slide over each other.