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Flashcards in C2.3 Deck (33)
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0
Q

Are the melting and boiling points of simple molecular structures low or high?

A

Low

1
Q

Are the forces weak or strong in simple molecular structures?

A

Weak

2
Q

Are simple molecular structures made from non-metal or metal elements?

A

Non-metals

3
Q

What are giant ionic structures made from?

A

Ions

4
Q

Are the ions in giant ionic structures held together by strong or weak bonds?

A

Weak

5
Q

Are the melting and boiling points of giant ionic structures or salts high or low?

A

High

6
Q

Is a lot of energy needed to break the bonds in giant ionic structures?

A

Yes

7
Q

Are the ions arranged regularly or irregularly in a giant ionic structure?

A

Regularly

8
Q

Why do giant ionic structure only conduct electricity in a solution or if molten?

A

The ions are free to move.

9
Q

Give an example of a giant molecular structure

A

Diamond

10
Q

What kind of bonds are in giant molecular structures?

A

Strong covalent bonds

11
Q

Is a lot of energy needed to separate the carbon atoms in a diamond?

A

Yes

12
Q

Does diamond have a high boiling and melting point?

A

Yes

13
Q

Does diamond dissolve in water?

A

No

14
Q

Name another giant molecular structure

A

Graphite

15
Q

How are the layers of graphite held together?

A

With strong forces of attraction

16
Q

Giant metallic structures have a) negative or b) positive electrons in a sea?

A

Negative

17
Q

How do the charges on the metal ions and electrons hold the ions together?

A

There is a strong attraction between the positive metal ions and the negative electrons.

18
Q

Give three properties of thermo-setting polymers

A

Solid, hard, rigid

19
Q

Do thermo-setting polymers have cross links the hold the chains together?

A

Yes

20
Q

Do thermo-softening polymers have cross links between the chains?

A

No

21
Q

Give a property of a thermo-setting polymer and explain why it works

A

Easy to mould because the forces between the chains are easy to overcome

22
Q

How is low-density polyethene made?

A

By heating ethene at 200’c under high pressure

23
Q

Give a property of low density polyethene

A

Flexible

24
Q

Give uses of low density polyethene

A

Bags and bottles

25
Q

How is high density poly ethene made?

A

With a lower temperature and pressure in the presence of a catalyst

26
Q

Give a property of high density polyethene

A

Rigid

27
Q

Give a use of high density polyethene

A

Water tanks

28
Q

What is an alloy

A

Two metals mixed to have the best possible properties

29
Q

What are nano particles?

A

Very small particles

30
Q

What are fullerenes?

A

Molecules of carbon arranged in hexagonal rings.

31
Q

What kind of bonding is involved in carbon atoms when making carbon nanotubes?

A

Covalent

32
Q

Do nano particles have a small or large surface area to volume ratio?

A

Large