Structure and Bonding

Question 1

Define a compound

Answer 1

Two or more elements which are chemically combined

Question 2

What is the special group of elements that are stable and extremely unreactive?

Answer 2

The noble gases

Question 3

When atoms share electrons what type of bonding is this?

Answer 3

Covalent

Question 4

When atoms permanently give electrons what type of bonding is this?

Answer 4

Ionic

Question 5

In ionic bonding when atoms lose or gain electrons they create particles called __________

Answer 5

Ions

Question 6

During ionic bonding what happens to the protons?

Answer 6

There is one more proton in the nucleus than electrons around on the outer shell

Question 7

When non metals react with metals which one gains electrons and why?

Answer 7

The non metal atom gains electrons to get a full outer shell

Question 8

Which bond is it when a group 7 element steals an electron from a group 1 element?

Answer 8

Ionic bond

Question 9

What does metallic bonding contain

Answer 9

a delocalised cloud of electrons

Question 10

What are delocalised electrons?

Answer 10

free electrons

Question 11

What type of force holds the ions together in an ionic compound?

Answer 11

electrostatic forces of attraction

Question 12

Why do ionic compounds have a high boiling and melting point?

Answer 12

They take lots of energy to break up

Question 13

Why can’t a solid ionic compound conduct electricity?

Answer 13

It’s ions are held in a fixed position and can’t move around

Question 14

What force is between molecules in covalent bonding?

Answer 14

intermolecular forces

Question 15

What are diamond and silicone both examples of?

Answer 15

strong covalent structures

Question 16

Give three properties of strong covalent structures

Answer 16

Hard
High melting and boiling points
Insoluble in water

Question 17

Why do the layers in Graphite slide over so easily?

Answer 17

There are weak intermolecular forces between they layers

Question 18

What can we make with chemicals from crude oil?

Answer 18

polymers

Question 19

What joins together to make polymers?

Answer 19

monomers

Question 20

What do the properties of a polymer depend on?

Answer 20

The monomers used

The conditions chosen

Question 21

What types of two polyethene are there?

Answer 21

HD and LD (Density)

Question 22

Why are both types of polyethene different?

Answer 22

They are made in different conditions

Question 23

How is a low density polyethene formed? (2 Marks)

Answer 23

With Lots of pressure (1 mark) and some oxygen ethene forms polyethene (1 mark)

Question 24

How is a high density polyethene formed? (2 Marks)

Answer 24

With a catalyst at 50 degrees and a slightly raised pressure ethene forms polyethene

Question 25

What are thermosoftening polymers?

Answer 25

Polymers that soften quite easily and reset when they cool down

Question 26

What are thermosetting polymers?

Answer 26

Polymers that do not melt when we heat them

Question 27

Which polymer has strong covalent bonds?

Answer 27

thermosetting polymers

Question 28

Give two risks of nanoscience

Answer 28

1. Their large surface area makes them good catalysts | 2. Using them too much could result in them being in the air.

Question 29

What group do ions have the structure of?

Answer 29

Noble gases

Question 30

When halogens react with alkalis what is formed?

Answer 30

Ionic compounds

Question 31

When halogens react with alkalis, what charge do the halide ions have?

Answer 31

A single negative charge

Question 32

Name two covalent structures.

Answer 32

Diamond and silicone dioxide

Question 33

What are electrons in the outer shell of a metal atom?

Answer 33

Delocalised

Question 34

If electrons are delocalised what does this mean?

Answer 34

They're free to move

Question 35

What are some substances that consist of simple molecules?

Answer 35

Gases, solids and liquids with low boiling and melting points

Question 36

What kind of force do substances with simple molecules have?

Answer 36

Intermolecular forces (weak forces)

Question 37

When a substance boils or melts, what is overcome? The covalent bond or the intermolecular forces?

Answer 37

The intermolecular forces

Question 38

Why don't substances that consist of simple molecules conduct electricity?

Answer 38

The molecules do not have an overall charge

Question 39

What kind of melting and boiling point to ionic structures have?

Answer 39

High melting and boiling point

Question 40

Can ionic compounds conduct electricity when melted or under water? If yes, why?

Answer 40

Yes they can, the ions are free to move and can carry the current

Question 41

What kind of melting point does a covalent bond have?

Answer 41

A high melting point

Question 42

In diamond how many covalent bonds are formed?

Answer 42

4 bonds with other carbon atoms

Question 43

What makes diamond so strong?

Answer 43

The 4 covalent bonds with other carbon atoms that it has

Question 44

In graphite each carbon bonds to...

Answer 44

3 other carbon

Question 45

In graphite when carbon bonds to three others what does this form?

Answer 45

Layers

Question 46

Why can the layers slide over each other in a covalent structure?

Answer 46

Because there are no covalent bonds between the layers so graphite is soft and slippery

Question 47

In graphite what is different about each carbon atom?

Answer 47

One electron from each carbon atom is delocalised

Question 48

What do the delocalised electrons in graphite help with?

Answer 48

Conduct heat and electricity

Question 49

What can carbon form with different numbers of carbon atoms?

Answer 49

Fullerenes

Question 50

Give 4 things fullerenes can be used for?

Answer 50

- Drug delivery - Lubricants - Catalysts - Nanotubes

Question 51

Why can metals be bent and shaped?

Answer 51

Because the layers of atoms in metals are able to slide over each other

Question 52

Why are alloys harder than pure metals?

Answer 52

The different sized atoms of the metals distort the layers in the structure, making it more difficult for them to slide over each other

Question 53

What can shape memory alloys do after being deformed?

Answer 53

Return to their normal shape

Question 54

What do Thermosoftening polymers consist of?

Answer 54

Individual tangled polymer chains

Question 55

Why don't thermosetting polymers melt when heated?

Answer 55

They have polymer chains with cross-links between | them to prevent melting