C2: Bonding,structure And The Properties Of Matter Flashcards Preview

GCSE Chemistry > C2: Bonding,structure And The Properties Of Matter > Flashcards

Flashcards in C2: Bonding,structure And The Properties Of Matter Deck (79):
1

What is a molecule?

When atoms of the same element join together we get a molecule of that element.

2

What are the three types of strong chemical bonds?

Covalent, ionic and metallic

3

What are the particles like in ionic bonding?

The particles are oppositely charged ions

4

What are the particles like in covalent bonding?

The particles are atoms that share pairs of electrons

5

What are the particles like in metallic bonding?

The particles are atoms that share delocalised electrons

6

Where does ionic bonding occur?

It occurs in compounds that combine metals with non metals

7

Where does covalent bonding occur?

It occurs in most non-metallic elements and in compounds of non metals

8

Where does metallic bonding occur?

It occurs in metallic elements and alloys

9

In ionic bonding when a metal reacts with a non metal what happens?

Electrons in the outer shell of the metal atom are transferred

10

What happens when metal atoms lose electrons?

They become positively charged ions

11

What happens when a non metal gains electrons?

They become negatively charged ions

12

What ions that are produced have the same electronic structure as a noble gas?

Ions produced by metals in group 1 and 2 and by non metals in group 6 and 7

13

What is an ionic compound?

A giant structure of a ions

14

How are ionic compounds held together?

By strong electrostatic forces of attraction between oppositely charged ions

15

In which direction do the strong electrostatic forces act in an ionic bond?

They act in ALL directions

16

Q image thumb

structure of sodium chloride

17

Q image thumb

structure of sodium chloride

18

When atoms share pairs of electrons they form...

Covalent bonds

19

What may covalently bonded substances consist of?

Small molecules

20

Though some covalently bonded substances may have very large molecules like...

polymers

21

Some covalently bonded substances have giant covalent structures like...

Diamond and silicon dioxide

22

Metals consist of...

giant structures of atoms arranged in a regular pattern

23

The electrons in the outer shell of a metal atom are....

Delocalised and so are free to move around

24

Sharing of delocalised electrons gives rise to...

Strong metallic bonds

25

Where does freezing and melting take place at?

Melting point

26

Where does boiling and condensing take place at?

Boiling point

27

What does the amount of energy need to change the state depend on?

The strength of the forces between the particles (In solids there are strong forces where in gases there are very weak forces)

28

The stronger the forces...

The higher the melting point and boiling point

29

What does the nature of the particles depend on?

The type of bonding and structure of the substance

30

What happens to the substance and the bonds between the particles when its being heated?

When a substance is heated, the temperature transfers energy to the particles until it reaches a point where it has enough energy to break the bonds meaning it changes state

31

What does the symbol (S) mean?

solid

32

What does the symbol (l) mean?

liquid

33

What does the symbol (g) mean?

gas

34

What does the symbol (aq) mean?

aqueous solution

35

What are the structures like for ionic compounds?

Giant ionic lattices

36

What are the forces of attraction like in ionic compounds?

They have strong electrostatic forces of attraction in all directions between oppositely charged ions

37

Why do ionic compound have high melting and boiling points?

Because large amounts of energy are needed to break the strong bonds

38

When and Why do ionic compounds conduct electricity?

When they are melted or dissolved in water the ions are free to move around so charge can flow

39

Substances that consist of small molecules are usually...

liquids or gases that have relatively low melting and boiling points

40

Why do substances consisting of small molecules have low melting and boiling points despite having strong covalent bonds?

They have weak intermolecular forces

41

How do intermolecular forces get bigger?

When the molecules get bigger so larger molecules have higher melting and boiling points

42

simple molecular substances have strong covalent bonds True or false?

true

43

Do substances with small molecules conduct electricity?

No as they do not have an overall electric charge so there are no free ions

44

What needs to be overcome in order for the simple molecular substance to change state?

the intermolecular forces not the covalent bonds

45

How big are molecules in polymers?

Polymers have very large molecules

46

How are the atoms joined together in a polymer?

by very strong covalent bonds

47

Are the intermolecular forces between the molecules strong?

Yes the intermolecular forces are relatively strong

48

What state is a polymer in at room temperature?

solid

49

Q image thumb

polymer diagram

50

Substances that consist of giant covalent structures are...

solids with very high melting points

51

How are atoms linked in giant covalent structures?

Strong covalant bonds that need to be overcome to melt or boil these substances 

52

Name some examples of giant covalent structures

Diamond and graphite(forms of carbon) , sillicon dioxide (sillica)

53

Diagrams of giant covalent structures -

 need to be able to recognise them

A image thumb
54

Metals have...

giant structures of atoms with strong metallic bonds which means most metals have high melting and boiling points 

55

How are atoms arranged in pure metals?

They're arranaged in layers which allow them to be bent and shaped 

56

Why are pure metals mixed with other metals?

To make alloys which are harder as pure metals are too soft for many uses 

57

Why are alloys harder than pure metals?

Different elements have different size atoms so when when another element is mixed with a pure metal, the new atosm will distort the layers making it harder for them to slide over each other making the alloy harder 

58

Why are metals good conductors of electricity?

They have delocolised electrons that carry electrical charge through the metal

59

Whya re metals good conductors of thermal energy?

Energy is transferred by the delocalised electrons 

60

In a diamond each carbon atom...

forms four covalent bonds with other carbon atoms in a giant covalent structure 

61

Is diamond very hard?

                                             yes 

62

Does diamond conduct electricity?

no because there are no free ions or electrons

63

Does diamond have high melting point?

yes because there are strong covalent bonds 

64

              Does graphite conduct electricty and thermal energy?

One electron from each carbon atom is delocalised so yes  

This makes it similar to metals as metals have delocalised electrons 

 

65

In graphite each carbon atom forms...

Three covalent bonds woth other carbon atoms , forming layers of hexagonal rings which have no covalent bonds between the layers 

66

Why is graphite ideal as a lubricating material>?

The layers are held together weakly meaning they're free to move over each other 

This makes it soft amd slippery 

67

Has graphite got a high melting point?

Yes because there are strong covalent bonds in the layers 

68

 

Graphene is a sheet....

 

of carbon atoms joined togther in hexagons 

69

Explain the properties of graphene in terms of its structure and bonding.

-The network of carbon atoms makes it very strong but as its only one atom thick its also very light

70

What is graphene useful for ?

how?

electronics  because it contains delocalised electrons which conduct electricity through the whole structure 

- also composites because the arrangement of the carbon atoms makes it strong but also as it's one atom thick its also very light so it can improve strength without adding weight

71

describe a graphene diagram

A image thumb
72

What are fullerenes?

molecules of carbon atoms shaped like hollow balls

73

what is the structure of fullerenes based on?

hexagonal rings of carbon atoms but also may contain rings of 5 or 7 atoms

74

what was the first fullerene to be discovered?

Buckministerfullerene (spherical shape)

75

Can fullerenes form nanotubes?

Yes

76

what are nanotubes?

They are carbon cylindrical fullerenes with very high length top diameter ratios

77

Why are nanotubes useful?

Nanotubes can conduct electricity and heat

they are also very light

they have a very high tensile strength

they can be used in electronics because of this 

they can add strength to an object without adding weight such as tennis racket frames 

78

What are the uses of fullerenes?

-can deliver drugs as tehy can 'cage' other molecules 

-can be used as lubricants 

-carbon nanotubes (nanotechnology)

79

Q image thumb

 the structure of fullerenes