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GCSE Chemistry > C3 - Structure and Bonding > Flashcards

C3 - Structure and Bonding Flashcards

1
Q

What is an alloy?

A

A mixture of two or more elements, at least one of which is a metal

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2
Q

What is a Covalent bond?

A

the bond between two atoms that share one or more pairs of electrons

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3
Q

What is covalent bonding?

A

the attraction between two atoms that share one or more pairs of electrons

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4
Q

What is a delocalised electron?

A

bonding electron that is no longer associated with any one particular atom

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5
Q

What is a dot and cross diagram?

A

a drawing to show only the arrangement of outer shell electrons of the atoms or ions in a substance

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6
Q

What is a fullerene?

A

Carbon allotropes which exist in the form of large, hollow, spherical molecules in a cage-like strucuture. Based on hexagonal rings of carbon atoms

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7
Q

What are gases?

A

substances that have no fixed shape or volume and can be compressed easily

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8
Q

What is a giant covalent structure?

A

a huge 3D network of covalently bonded atoms

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9
Q

What is a giant lattice?

A

a huge 3D network of atoms or ions

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10
Q

What is a giant structure?

A

a huge 3D network of atoms or ions

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11
Q

What are intermolecular forces?

A

the attraction between the individual molecules in a covalently bonded substance

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12
Q

What is an ionic bond?

A

the electrostatic force of attraction between positively and negatively charged ions

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13
Q

What is a liquid?

A

substances that have a fixed volume, but they can flow and change their shape

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14
Q

What is nanoscience

A

the study of very tiny particles or structures between 1 and 100 nanometres in size

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15
Q

What is particle theory?

A

a theory that explains the properties of solids, liquids and gases based on the fact that all matter is made from tiny particles. It describes the movement of particles and the distance between them

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16
Q

What is a polymer?

A

a substance made from very large molecules made up of many repeating units

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17
Q

What are solids?

A

substances that have a fixed shape and volume that cannot be compressed. the particles cannot move, only vibrate

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18
Q

What is states of matter?

A

the forms in which matter can exist. A substance can be solid, liquid or gas

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19
Q

In melting and boiling the energy is transferred from ……… to the …………

A

In melting and boiling the energy is transferred from the surroundings to the substance

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20
Q

In freezing and condensing the energy is transferred from ……… to the …………

A

In freezing and condensing the energy is transferred from substance to the surroundings

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21
Q

What are the limitations of particle theory?

A

The particle model is limited as it assumes particles are solid spheres with no forces between them, however particles can be atoms, molecules or ions. They can vary in size. They can contain many atoms and they are not solid or spherical.

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22
Q

What is covalent bonding?

A

Covalent bonding is the electrostatic attraction between a shared pair of electrons and the nuclei of 2 atoms. (When 2 atoms share a pair of electrons)

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23
Q

What is Ionic bonding?

A

Ionic bonding is the electrostatic attraction between oppositely charged ions

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24
Q

What type of elements form positive ions?

A

metals

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25
Q

What type of elements form negative ions?

A

non-metals

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26
Q

What do dot and cross diagrams show?

A

the electron transfer during the formation of an ionic compound

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27
Q

What is the arrangement of ionic bonding?

A

a giant lattice structure

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28
Q

What is the conductivity of ionic bonds as a solid?

A

they do not conduct

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29
Q

What is the conductivity of ionic bonds as a liquid?

A

they can conduct

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30
Q

What is an ion?

A

A charged atom formed by the loss or gain of electrons

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31
Q

Why do atoms lose or gain electrons to form ions?

A

To obtain a full outer shell of electrons

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32
Q

What are negative ions called?

A

Anions

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33
Q

What are positive ions called?

A

Cations

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34
Q

What is the formula of Lithium?

A

Li¹+

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35
Q

What is the formula of Potassium?

A

K¹+

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36
Q

What is the formula of Silver?

A

Ag¹+

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37
Q

What is the formula of Magnesium?

A

Mg²+

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38
Q

What is the formula of Copper?

A

Cu²+

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39
Q

What is the formula of Aluminium?

A

Al³+

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40
Q

What is the formula of Chromium?

A

Cr³+

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41
Q

What is the formula of Ammonium?

A

NH₄¹+

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42
Q

What is the formula of Fluoride?

A

F¹-

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43
Q

What is the formula of Bromide?

A

Br¹-

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44
Q

What is the formula of Hydroxide?

A

OH¹-

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45
Q

What is the formula of Chloride?

A

Cl¹-

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46
Q

What is the formula of Nitrate?

A

NO₃¹-

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47
Q

What is the formula of Sulfate?

A

SO₄²-

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48
Q

What is the formula of Carbonate?

A

CO₃²-

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49
Q

What is the structure of an ionic compound?

A

Giant Lattice

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50
Q

What state are ionic compounds at room temperature?

A

Solid

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51
Q

Why do ionic compounds have a high melting point?

A

Lots of energy is required to break every ionic bond

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52
Q

In what state do ionic compounds conduct?

A

Liquid/aqueous solution

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53
Q

Why do ionic compounds only conduct as a liquid or an aqueous solution?

A

Ionic compounds contain charged particles but the particles are not free to move as a solid as they are fixed in a lattice, when molten these particles can move freely and can conduct

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54
Q

What does the formula Na₂S mean?

A

the ionic compound Sodium Sulphate has Sodium ions and Sulphur ions in the ratio 2:1

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55
Q

What is a molecule?

A

A substance made up of non-metal atoms joined by covalent bonds

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56
Q

When are covalent bonds formed?

A

When atoms share a pair of electrons

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57
Q

What are the advantages of using dot and cross models to represent molecules?

A

They are useful for illustrating sharing/transfer of electrons. They indicate which atoms the shared electrons have come from.

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58
Q

What are the disadvantages of using dot and cross models to represent molecules?

A

They fail to illustrate the 3d arrangement of the atoms and the electron shells. They do not indicate the relative size of atoms and subatomic particles.

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59
Q

What are the advantages of using 3d “stick” representation of molecules?

A

They are useful for illustrating the arrangements of atoms in 3d space. They are very useful for visualising the shape of the molecule

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60
Q

What are the disadvantages of using 2d “stick” representation of molecules?

A

They fail to indicate the movement of electrons. The atoms are placed far apart from each other, which in reality is not the case as the gaps between atoms are much smaller.

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61
Q

ions are formed when what type of elements react?

A

metals and non-metals

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62
Q

What type of elements lose electrons?

A

metals

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63
Q

What type of elements gain electrons?

A

non-metals

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64
Q

Explain what the formula Al₂O₃ tells us about aluminium oxide?

A

The ionic compound of Aluminium Oxide contains Aluminium ions and Oxygen ions in the ratio 2:3

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65
Q

Aluminium oxide has a very high melting point while carbon dioxide has a very low melting point. Explain this difference.

A

Aluminium oxide is ionically bonded and therefore has many strong ionic bonds between each ion. For it to melt every bond needs to be broken and therefore a lot of energy is required whereas Carbon Dioxide has simple molecular bonding and therefore has a low melting point as it has weak intermolecular forces between each molecule which do not require much energy to break.

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66
Q

Carbon dioxide does not conduct electricity in any state whereas aluminium oxide will conduct electricity when it is molten. explain this difference.

A

For a substance to conduct it needs to have mobile charged particles. Carbon dioxide is covalently bonded and therefore does not have any charged particles. That means that the carbon dioxide cannot conduct in any state. Aluminium oxide is ionically bonded which means that it does have charged particles. When it is in a solid state it does not have “mobile particles” as it is fixed in a lattice and therefore cannot conduct, however when molten it does have charged particles that are free and can therefore conduct.

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67
Q

Explain why ammonia has a low melting point.

A

Ammonia has a simple molecular structure, this means that it has weak intermolecular forces and very little force is required to break these bonds.

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68
Q

Explain why diamond is hard but graphite is soft.

A

Diamond has a giant covalent lattice and each carbon atom is bonded to 4 other carbon atoms. On the other hand, graphite is formed in layers and each carbon atom is bonded to only 3 other carbon atoms. This causes graphite to be soft as the layers of graphene can slide off of each other

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69
Q

Why does graphite conduct but diamond cannot?

A

For a substance to conduct it needs to have mobile charged particles. Diamond is covalently bonded and it does not have any delocalised electrons, this means that diamond does not have any mobile charged particles and cannot conduct. Whereas graphite is formed in layers and each carbon atom is bonded to only 3 other carbon atoms. This causes there to be an extra unbonded electron, thus forming a sea of delocalised electrons. These delocalised electrons are free to move and they are charged. This means that graphite can conduct.

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70
Q

What do dots/crosses represent in a dot and cross diagram?

A

electrons

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71
Q

What is the structure type of Diamond?

A

Giant Covalent

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72
Q

What is the structure type of Graphite?

A

Giant Covalent

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73
Q

What is the structure type of Buckminsterfullerene?

A

Simple Molecular

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74
Q

What is the structure type of Graphene?

A

Giant Covalent

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75
Q

What is the formula of Diamond?

A

C

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76
Q

What is the formula of Graphite?

A

C

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77
Q

What is the formula of Buckminsterfullerene?

A

C₆₀

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78
Q

What is the formula of Graphene?

79
Q

What is the Number of covalent bonds for each C atom for diamond

80
Q

What is the Number of covalent bonds for each C atom for graphite

81
Q

What is the Number of covalent bonds for each C atom for Buckminsterfullerene

82
Q

What is the Number of covalent bonds for each C atom for Graphene

83
Q

What is the melting/boiling point for diamond?

84
Q

What is the melting/boiling point for graphite?

85
Q

What is the melting/boiling point for Buckminsterfullerene?

A

not very high

86
Q

What is the melting/boiling point for Graphene?

87
Q

What is the reason for the melting/boiling point for diamond?

A

Need to break many strong covalent bonds

88
Q

What is the reason for the melting/boiling point for graphite?

A

Need to break many strong covalent bonds

89
Q

What is the reason for the melting/boiling point for Buckminsterfullerene?

A

Only need to break relatively weak intermolecular forces

90
Q

What is the reason for the melting/boiling point for Graphene?

A

Need to break many strong covalent bonds

91
Q

What is the electrical conductivity of diamond?

92
Q

What is the electrical conductivity of graphite?

93
Q

What is the electrical conductivity of Buckminsterfullerene?

94
Q

What is the electrical conductivity of Graphene?

95
Q

What is the reason for the electrical conductivity of diamond?

A

has no delocalised electrons

96
Q

What is the reason for the electrical conductivity of graphite?

A

has delocalised electrons

97
Q

What is the reason for the electrical conductivity of Buckminsterfullerene?

A

Has delocalised electrons but they cannot move from 1 molecule to another

98
Q

What is the reason for the electrical conductivity of graphene?

A

has delocalised electrons.

99
Q

What is the strength of diamond?

A

very strong and hard

100
Q

What is the strength of graphite?

A

soft and brittle

101
Q

What is the strength of buckminsterfullerene?

A

soft and brittle

102
Q

What is the strength of graphene?

A

extremely strong

103
Q

What is the structure of graphite?

A

layers of graphene with weak forces between layers

104
Q

What is the structure of Buckminsterfullerene?

A

a spherical molecule with the formula of C₆₀

105
Q

What are nanotubes?

A

Thin tubes made of rolled up graphene, their length is much greater than their diameter

106
Q

As particles decrease in size their surface area …………. in relation to their volume

A

As particles decrease in size their surface area Increases in relation to their volume

107
Q

What is the formula for surface area to volume ratio?

A

Surface area to volume ratio = surface area / volume

108
Q

What is the main industrial application of nanoparticles?

109
Q

Why are nanoparticles used as catalysts?

A

They have a high surface area : volume ratio

110
Q

What are the main risks of nanoparticles?

A

The use of nanoparticles in science is in its early stages so there are still a lot of unknown factors and potential risks. In particular there is a lack of understanding on how they may affect health, particularly in the long term. Even a small amount of toxicity in a particular nanoparticle would be multiplied due to the high surface area to volume ratio. This coupled with the fact that they are not easily disposed of by the body are a cause for caution in the medical application of nanoparticles.

111
Q

A cube has sides of 8nm. What is the surface area to volume ratio of the cube?

112
Q

What is the electrical conductivity of an ionic compound as a liquid?

113
Q

What is the electrical conductivity of a metallic substance as a liquid?

114
Q

What is the electrical conductivity of a covalent substance as a liquid?

A

does not conduct

115
Q

What is the electrical conductivity of an ionic compound as a solid?

A

does not conduct

116
Q

What is the electrical conductivity of a metallic substance as a solid?

117
Q

What is the electrical conductivity of a covalent substance as a solid?

A

does not conduct

118
Q

What is the melting/boiling point of a simple molecular structure?

119
Q

What is the electrical conductivity of a simple molecular structure?

A

Does not conduct

120
Q

What is the strength of a simple molecular structure?

121
Q

What is the reason for the melting/boiling point of a simple molecular structure?

A

weak intermolecular forces

122
Q

What is the reason for the electrical conductivity of a simple molecular structure?

A

They do not have any mobile charged particles

123
Q

What is the reason for the strength of a simple molecular structure?

A

weak intermolecular forces

124
Q

What is the formula for Silicon Dioxide?

125
Q

What are the 3 giant covalent structures?

A

Diamond, Silicon Dioxide, Graphite

126
Q

What is the melting point of diamond and silicon dioxide?

127
Q

What is the electrical conductivity of diamond and silicon dioxide?

A

does not conduct

128
Q

What is the strength of diamond and silicon dioxide?

129
Q

What is the reason for the melting point of diamond and silicon dioxide?

A

MANY strong covalent bonds so lots of energy is required to break these bonds

130
Q

What is the reason for the electrical conductivity of diamond and silicon dioxide?

A

No mobile charged particles

131
Q

What is the reason for the strength of diamond and silicon dioxide?

A

Rigid arrangement of atoms held in place by covalent bonds

132
Q

Why is graphite used as pencil lead?

A

the layers can slide off of each other and stay on the paper, they are also a different colour to the paper

133
Q

What is the melting point of graphite

134
Q

What is the electrical conductivity of graphite

135
Q

What is the strength of graphite

136
Q

What is the reason for the melting point of graphite

A

need to break all strong covalent bonds

137
Q

What is the reason for the electrical conductivity of graphite

A

they have delocalised electrons that are free to move between layers

138
Q

What is the reason for the strength of graphite

A

weak forces between layers so layers can slide

139
Q

What type of element are simple molecular substances made out of?

A

non-metals

140
Q

What is a metallic structure?

A

A GIANT LATTICE, the outer shell of electrons is delocalised leaving a lattice of positive ions. These delocalised electrons attract and are attracted to the positive ions

141
Q

What is a metallic bond?

A

The electrostatic force of attraction between positive ions and negative delocalised electrons

142
Q

How many delocalised electrons will there be per atom in a group 1 metal?

143
Q

How many delocalised electrons will there be per atom in a group 2 metal?

144
Q

How many delocalised electrons will there be per atom in a group 3 metal?

145
Q

Which group of metal elements will have the strongest metallic bond?

A

Group 3 metals as they have the most delocalised electrons, this means that the electrostatic force between the electrons and the ions is increased.

146
Q

What is the melting/boiling point in metals?

147
Q

What is the electrical conductivity in metals?

148
Q

What is the thermal conductivity in metals?

149
Q

What is the strength of metals?

150
Q

What is the malleability of metals?

151
Q

What is the reason for the melting/boiling point in metals?

A

They have high melting points as they have many strong metallic bonds that need to be broken for them to melt/evaporate. This means that lots of energy is required to break all these bonds

152
Q

What is the reason for the electrical conductivity in metals?

A

It has delocalised electrons that can move freely throughout the lattice structure

153
Q

What is the reason for the thermal conductivity in metals?

A

It has delocalised electrons that can move freely throughout the lattice structure

154
Q

What is the reason for the strength of metals?

A

It has many strong metallic bonds between each molecule that require a lot of energy to break

155
Q

What is the reason for the malleability of metals?

A

The movement of the lattice does not cause the molecules to repel each other.

156
Q

What is an alloy?

A

An alloy is a substance that is a mixture of different elements that contains at least 1 metal. The different sized atoms disrupt the regular arrangement of the metals

157
Q

Why are alloys more useful than the pure metal?

A

By mixing different metals you can combine their useful properties and due to atoms of different sizes it distorts the regular arrangement. By mixing metals it makes them stronger, harder and could give them more resistance to corrosion.

158
Q

What is the melting and boiling points of monatomic substances?

159
Q

What is the melting and boiling points of ionic substances?

160
Q

What is the melting and boiling points of simple molecular substances?

161
Q

What is the melting and boiling points of giant covalent substances?

162
Q

What is the melting and boiling points of metallic substances?

163
Q

What is the conductivity as a solid of monatomic substances?

A

does not conduct

164
Q

What is the conductivity as a solid of ionic substances?

A

Does not conduct

165
Q

What is the conductivity as a solid of simple molecular substances?

A

does not conduct

166
Q

What is the conductivity as a solid of giant covalent substances?

A

does not conduct

167
Q

What is the conductivity as a solid of metallic substances?

168
Q

What is the conductivity when melted of monatomic substances?

A

does not conduct

169
Q

What is the conductivity when melted of ionic substances?

170
Q

What is the conductivity when melted of simple molecular substances?

A

does not conduct

171
Q

What is the conductivity when melted of giant covalent substances?

A

does not conduct

172
Q

What is the conductivity when melted of metallic substances?

173
Q

What is the solubility in water of monatomic substances?

174
Q

What is the solubility in water of ionic substances?

A

soluble (usually)

175
Q

What is the solubility in water of simple molecular substances?

A

Insoluble (usually)

176
Q

What is the solubility in water of giant covalent substances?

177
Q

What is the solubility in water of metallic substances?

178
Q

What is the conductivity of a solution of monatomic substances?

179
Q

What is the conductivity of a solution of ionic substances?

180
Q

What is the conductivity of a solution of simple molecular substances?

A

insoluble (usually)

181
Q

What is the conductivity of a solution of giant covalent substances?

182
Q

What is the conductivity of a solution of metallic substances?

183
Q

What is a fullerene?

A

a fullerene is a large spherical molecule made from carbon

184
Q

What is a cylindrical fullerene called?

A

A nanotube

185
Q

What size range does nanoscience deal with?

A

between 1 and 100nm

186
Q

What is the empirical formula?

A

a formula giving the proportions of the elements present in a compound but not the actual numbers or arrangement of atoms.

187
Q

What are intramolecular forces?

A

An intramolecular force is any force that binds together the atoms making up a molecule or compound

188
Q

What is the difference between intermolecular forces and intramolecular forces

A

An intramolecular force is any force that binds together the atoms making up a molecule or compound, not to be confused with intermolecular forces, which are the forces present between molecules

189
Q

What is an ion of oxygen called?

190
Q

Why is buckminsterfullerene a good lubricant?

A

In buckminsterfullerene the molecules are spherical so the molecules will roll over each other

191
Q

What are the 3 types of intramolecular forces?

A
  • Ionic
  • Covalent
  • Metallic
192
Q

What are the 5 different structure types of a substance?

A
  • Giant Covalent
  • Ionic
  • Metallic
  • Molecular
  • Monatomic
193
Q

What are the 5 different structure types of a substance?

A
  • Giant Covalent
  • Ionic
  • Metallic
  • Molecular
  • Monatomic
194
Q

Where do you draw the electrons in a dot and cross diagram for covalent bonds?

A

In the gap between the 2 electron shell

GCSE Chemistry (15 decks)

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