C3 - Structure and Bonding Flashcards
(91 cards)
1
Q
What is it called when a SOLID turns into a GAS
A
Sublimation
2
Q
What is it called when a SOLID turns into a LIQUID?
A
Melting
3
Q
What is it called when a LIQUID turns into a SOLID?
A
Freezing
4
Q
What is it called when a LIQUID turns into a GAS?
A
Boiling
5
Q
What is it called when a GAS turns into a SOLID?
A
Deposition
6
Q
What is it called when a GAS turns into a LIQUID?
A
condensing
7
Q
What is a covalent bond?
A
When electrons are shared between non metal atoms
8
Q
Why do atoms need full outershells?
A
To be stable
9
Q
What is the definition of Ionic Bonding?
A
The electrostatic force of attraction between two oppositely charged ions
10
Q
Why do lattices have very high melting and boiling points?
A
They have lots of ionic bonds
This means that the bonds are very strong
Requiring alot of energy to break
11
Q
What is the formula of hydroxide ions?
A
_
OH
12
Q
What is the formula of Sulfate?
A
2-
SO4
13
Q
What happens when two non metal elements try and attract? For example Cl and Cl
A
They share electrons
14
Q
Which types of elements combine in ionic bonding?
A
Metals combine with non metals
15
Q
Why do metals combine with non metals in ionic bonding? For example, Li and Cl
A
So both elements can have a full outer shell
Li (+1) + Cl (-1) = LiCl
16
Q
What is an ionic compound?
A
A giant structure of ions
17
Q
How are ionic compound held together?
A
Electrostatic forces of attraction between oppositely charged ions (ionic bonding)
18
Q
What happens when ionic compounds are melted or dissolved in water?
A
They conduct electricity
19
Q
Why do ionic compounds conduct electricity when melted or dissolved in water?
A
The ions are free and their charge can flow
20
Q
Where does covalent bonding occur?
A
Between non - metal elements and compounds of non metals
21
Q
How are covalent bonds formed?
A
When atoms share pairs of electrons
22
Q
What is metallic bonding?
A
Atoms which share delocalised electrons
23
Q
What are some examples of giant covalent structures?
A
Diamond
Graphite
24
Q
What is an example of a simple molecullar structure?
A
Water
25
Why do ionic substances not conduct electricicty when they are a solid?
The ions are in a fixed position and are not free to flow
26
What does it mean when an atom is delocalised?
It is free to move around the whole structure
27
Why do positive metal ions attract to delocalised elctrons?
Electrostatic force of attraction
28
What are the properties of giant covalents?
High melting and boiling points
29
What are the three main types of covalent structures?
Giant covalents
Small molecules
Large molecules
30
What are the properties of covalent small molecules?
Low melting and boiling poit
The intermolecular forces are weak so do not require energy
31
What are the properties of covalent large molecules?
Melting and boiling points are low but still stronger than small molecules
32
What is the state of giant covalents at room temperature?
Solid
33
What is the state of covalent small molecules at room temperature?
Gaseous or liquid
34
What is the state of covalent large molecules at room temperature?
Normally solid
35
Why do most covalent structures not conduct electricity?
They do not have delocalised electrons or ions that are free to move
36
What type of covalent structure is Graphite?
Giant Covalent
37
Can Graphite conduct electricity?
Yes
38
What is the structure of graphite in more depth?
Each carbon arom forms three covalent bonds to create Hexagonal layers
Layers are not covalently bonded so they slide
Each carbon atom has one delocalised electron
39
What is the structure of fullerenes in more depth?
Hollow sphere of carbon atoms held by weak intermollecular forces
40
What is an allotrope?
Different structural forms of the same element
41
What are the allotropes of carbon?
diamond, graphite, graphene and fullerene
42
What is the carbon structure in a diamond?
Each carbon atom is covalently bonded to 4 other carbon atoms
43
What are the uses of fullerene?
Industrial catalyst
To strengthen materials
Drug delivery
44
What is an alloy?
The resulting mixture of adding a different element to a pure metal to make it harder
45
How are ions made?
When electrons are transferred
46
What do atoms need to do to get a "stable electronic structure"?
loses or gains electrons
47
How do metals form ions?
They lose electrons from their outershell to form postive ions
48
How do non-metals form ions?
They gain electrons into their outershell to form negative ions
49
Which groups are most likely form ions?
Groups 1 & 2, and 6 & 7
50
What what type of ions do group 1 elements form?
1+ ions
51
What what type of ions do group 2 elements form?
2+
52
What what type of ions do group 6 elements form?
2-
53
What type of ions do group 7 elements form?
1-
54
What happens in ionic bonding?
When a metal and a non-metal react together
55
Why do metals and non-metals transfer electron in Ionic Bonding?
There oppositely charged ions are strongly attracted to each other by electrostatic forces
56
What is the name of the structure of ionic compounds?
A Giant ionic lattice
57
Why are the ions in a giant ionic lattice so strong?
Because of the electrostatic forces of attraction between oppositely charged ions (EXTREME STRENGTH)
58
What does the structure of a single crystal of sodium chloride look like?
one giant ionic lattice
A similar ratio of positive and negative ions
Very strong electrostaic forces of sttraction
59
What are the properties of solid ionic compounds?
High Melting and Boiling points (Electrostatic force of attraction)
Cant conduct electricity (ions are held in place)
60
Why are covalent bonds so strong?
The atoms are attracted to the shared pair of electrons by electrostatic forces
61
Why, in covalent bonding, do atoms share electrons in their outsrshells?
They have the highest energy levels
62
What are simple molecular substance made up of?
molecules that contain a few atoms joined together by covalent bonds
63
What are some examples of simple molecula substances?
Hydrogen
Chlorine
Oxygen
Nitrogen
64
Why do simple molecular substances have low melting and boiling points if they have strong covalent bonds?
The intermolecular forces between the covalent bonds are very weak
65
Why dont molecular compounds like H20 or CO2, conduct electricity?
They have no delocalised electrons
66
What are the properties of simple molecular substances?
Strong covalent bonds within the molecules held together by weak intermolecular forces
Very Low melting and boiling points
Dont conduct electricity
67
What is the diametere of a nanoparticle?
Between 1nm and 100nm
68
What ratio do nanoparticles have?
Large surface area to volume ratio
69
What are some uses of nano particles?
Nanomedicine
Making new catalysts
Tiny electric circuits
70
Why is nanomedicine popular?
nanoparticles are tiny so can be absorbed more easily by the body
This means they can deliver drugs right into the specific cells
71
Why are nanoparticles used in tiny electric circuits?
Some nanoparticles conduct electricity
72
What is a disadvantage of nanomedicine?
Long term effects on health arent fully understood as it is new
73
What are polymers?
Long chains of repeating units
74
What is an example of a polymer?
Poly(propene) - one of the main polymers in plastic
75
What is the molecular formula for Polypropene?
(C3H6)n
76
Each Polymer Molecule is made up of smaller units called ___________
Monomers
77
What type of bonds are within polymers?
Covalent bonds
78
What are you breaking when melting or boiling a Polymer?
The weak intermolecular forces
79
Why do Polymers have a higher melting point and boiling point than simple molecular substances even though they both have very weak intermolecular forces?
Polymers have a large surface area
So theres more intermolecular forces to break
80
Why do giant covalent structures have high melting and boiling points?
Alot of energy is needed to break the strong covalent bonds
81
Why dont giant covalent structures conduct electricity?
They dont contain charged particles - even when molten
82
Why does diamond have a very high melting point?
Many strong covalent bond
Require alot of energy to break
83
Why does diamond not conduct electricity?
No delocalised electrons
84
Why is graphite the only giant covalent structure that can conduct electricity?
Only three out of each carbons four outer electrons are used
So each carbon has one delocalised electron
85
What can graphite conduct?
Electricity and thermal energy
86
What is graphene
One layer of Graphite
87
Give an example of a fullerene molecular formula
C60
88
A molecule such as C70 can be used in medicine to move drugs around the body
Why is this C70 molecule suitable for this use?
Its a fullerene so its hollow and unreactive
Cage like structure to enclose drugs securely and carry them to specific cells
89
What is an ion?
Charged particles
90
Explain how the structure of graphene makes it useful in electronic applications and components.
strong and flexible covalent bonds
Has delocalised electrons to conduct electricity
Very thin which is ideal for flexibility
91
Describe how the bonding in metals allows for it to conduct electricity
They have delocalised electrons present in their metallic structure. And their atoms are arranged in regular layers.
This allows their delocalised electrons to move freely and easily through the structure
