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GCSE Combined Chemistry (Edexcel) > Topic 7 - Fuels and Earth Science COMPLETE PK > Flashcards

Topic 7 - Fuels and Earth Science COMPLETE PK Flashcards

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1
Q

1 What are the chemical symbols for the elements carbon and hydrogen?

A

C; H

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2
Q

2 What type of bond (ionic, metallic or covalent) is found in simple molecules?

A

covalent

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3
Q

3 What state (solid, liquid or gas) is crude oil at room temperature?

A

liquid

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4
Q

4 How many shared electrons are there in a covalent bond?

A

two

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5
Q

5 Which element forms long chains in simple polymers such as polyethene

A

carbon

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6
Q

6 Which type of compound only contains hydrogen and carbon atoms?

A

hydrocarbon

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7
Q

7 Are ‘petrochemicals’ made from petrol, rock or crude oil?

A

crude oil

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8
Q

8 How many years (hundreds, thousands or millions) does it take for crude oil to form?

A

millions

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9
Q

9 If something is not being made any more, is it described as ‘finite’ or as ‘non-renewable’?

A

finite

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10
Q

10 About how many litres of crude oil does the world use each second (180, 1800 or 180 000)?

A

180 000

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11
Q

11 Name the two elements found in hydrocarbons.

A

carbon; hydrogen

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12
Q

12 Crude oil is forming extremely slowly. Does this make it a finite resource or a non-renewable one?

A

finite

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13
Q

13 Petrol comes from crude oil. Give one use for petrol.

A

fuel for cars

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14
Q

14 Name the main hydrocarbon found in natural gas.

A

methane

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15
Q

15 Diesel oil is being used up faster than crude oil forms. Does this make it a finite resource or a non-renewable one?

A

non-renewable

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16
Q

16 Name the polymer formed from ethene, which comes from crude oil.

A

polyethene

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17
Q

17 Name the state change that occurs when a gas becomes a liquid.

A

condensing/condensation

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18
Q

18 What bonds or forces exist between molecules (ionic, covalent or intermolecular)?

A

intermolecular forces

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19
Q

19 Compared with metals, do simple molecules typically have high boiling points or low ones?

A

low

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20
Q

20 Name the method used to separate a mixture of two or more liquids with different boiling points.

A

fractional distillation

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21
Q

21 Give one typical use of fuel oil.

A

fuel for large ships/fuel for some power stations

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22
Q

22 Crude oil is a source of feedstock. Give one other type of useful substance from crude oil.

A

fuels

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23
Q

23 Is crude oil described as a finite resource or an infinite resource?

A

finite

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24
Q

24 Name a non-renewable fossil fuel obtained from crude oil.

A

petrol/kerosene/diesel oil/fuel oil

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25
Q

25 Name the main non-renewable fossil fuel in natural gas.

A

methane

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26
Q

26 What process is used to separate crude oil into useful mixtures?

A

fractional distillation

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27
Q

27 Give one use for the gases fraction from crude oil.

A

domestic heating/cooking

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28
Q

28 Which fraction is more easily ignited, bitumen or kerosene?

A

kerosene

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29
Q

29 Which fraction is more viscous, bitumen or kerosene?

A

bitumen

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30
Q

30 Which hydrocarbons have the greater boiling points, the ones with larger molecules or the ones with smaller molecules?

A

larger molecules

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31
Q

31 Which elements are present in hydrocarbon molecules?

A

carbon; hydrogen

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32
Q

32 What is the most abundant element in air?

A

nitrogen/N2

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33
Q

33 Which gas reacts with hydrocarbons when they burn?

A

oxygen/O2

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34
Q

34 Name one fossil fuel used in cars.

A

petrol/diesel oil

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35
Q

35 Name a gas produced when carbon burns.

A

carbon monoxide/carbon dioxide

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36
Q

36 What compound forms when hydrogen burns in air?

A

water

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37
Q

37 What is the main fossil fuel in natural gas?

A

methane

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38
Q

38 To get a roaring blue Bunsen burner flame, do you open or close the air hole?

A

open it

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39
Q

39 Which cells in the blood carry oxygen around the body?

A

red blood cells

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40
Q

40 What is the black solid element found in soot and smoke?

A

carbon

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41
Q

41 What are the products of the complete combustion of hydrocarbon fuels?

A

carbon dioxide; water

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42
Q

42 Which gas is produced during incomplete combustion, but not complete combustion, of hydrocarbon fuels?

A

carbon monoxide

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43
Q

43 What solid element is produced during the incomplete combustion of hydrocarbon fuels?

A

carbon

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44
Q

44 Name the fuel used for large ships and some power stations.

A

fuel oil

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45
Q

45 Which gas reacts with hydrocarbon fuels when they burn?

A

oxygen

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46
Q

46 What is the pH of pure water?

A

7

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47
Q

47 Name the gas formed when acids react with metals.

A

hydrogen (MASH)

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48
Q

48 Name the gas formed when acids react with calcium carbonate.

A

carbon dioxide (CASHOCO)

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49
Q

49 Name the most abundant gas in the air.

A

nitrogen

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50
Q

50 Name the solid yellow element placed below oxygen in group 6 of the period table.

A

sulfur

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51
Q

51 Name one hydrocarbon fuel used for cars.

A

petrol; diesel

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52
Q

52 Which fraction ignites more easily, kerosene or fuel oil?

A

kerosene

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53
Q

53 Which fraction contains hydrocarbon molecules with the longer molecules, gases or bitumen?

A

bitumen

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54
Q

54 Name the process used to separate crude oil into simpler, more useful mixtures.

A

fractional distillation

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55
Q

55 Name the homologous series to which ethane belongs.

A

alkanes

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56
Q

56 What are the two products of complete combustion of ethane?

A

carbon dioxide; water

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57
Q

57 What type of rain forms when sulfur dioxide, from some hydrocarbon fuels, dissolves in rainwater?

A

acid

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58
Q

58 Name the greenhouse gas released when any hydrocarbon fuel burns.

A

carbon dioxide

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59
Q

59 Which occupies the least volume, 1 kg of hydrogen gas or 1 kg of liquid hydrogen?

A

1 kg of liquid hydrogen

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60
Q

60 Is crude oil a finite resource or a renewable resource?

A

finite resource

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61
Q

61 Which common compound of carbon and oxygen is thought to have been an abundant gas in Earth’s early atmosphere?

A

carbon dioxide

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62
Q

62 What are the names of the Earth’s two nearest neighbouring planets?

A

Venus and Mars

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63
Q

63 Name the biological process that increases oxygen levels and reduces carbon dioxide levels in the atmosphere.

A

photosynthesis

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64
Q

64 What geological feature of a planet’s surface can give out large amounts of hot gas?

A

volcano

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65
Q

65 Name the physical process that describes changing a vapour into liquid.

A

condensation

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66
Q

66 What type of reaction occurs when a metal gains oxygen?

A

oxidation

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67
Q

67 How old do scientists think the Earth is: 4.5 billion years, 4.5 million years or 450 000 years?

A

4.5 billion years

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68
Q

68 What sort of rocks are formed from layers of deposited material?

A

sedimentary rocks

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69
Q

69 Which gaseous element forms most of the Earth’s atmosphere today?

A

nitrogen

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70
Q

70 Titan is an icy moon of Saturn. What is ice made of?

A

water

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71
Q

71 Where were the gases that formed the Earth’s early atmosphere released from?

A

volcanoes

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72
Q

72 What two compounds are thought to have formed most of the Earth’s early atmosphere?

A

water, carbon dioxide

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73
Q

73 What is the chemical test for carbon dioxide?

A

turns limewater milky/cloudy

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74
Q

74 What element forms most of the Earth’s atmosphere today?

A

nitrogen

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75
Q

75 Which element that makes up about 21% of the atmosphere of Earth today was not thought to be present in the atmosphere 4.5 billion years ago?

A

oxygen

76
Q

76 As the Earth evolved, chemical reactions with what element are thought to have slowed the release of oxygen to the atmosphere?

A

iron

77
Q

77 What gas given out by volcanoes is thought to have condensed to form oceans?

A

water vapour

78
Q

78 What factor has caused changes in Earth’s atmosphere but is not found on Venus or Mars?

A

life

79
Q

79 What process in plants releases oxygen?

A

photosynthesis

80
Q

80 What is the chemical test for oxygen?

A

relights a glowing splint

81
Q

81 The relighting of a glowing splint is the test for what gas?

A

oxygen

82
Q

82 Why did the formation of the Earth’s early oceans cause a decrease in atmospheric carbon dioxide concentrations?

A

the carbon dioxide dissolved in the water

83
Q

83 What do some sea creatures use dissolved carbon dioxide to help them do?

A

form shells

84
Q

84 What sort of chemical compound are shells made from: an oxide, a carbonate or a chloride?

A

carbonate

85
Q

85 What is the formula for calcium carbonate?

A

CaCO3

86
Q

86 What process in plants and algae causes a reduction of atmospheric carbon dioxide concentrations?

A

photosynthesis

87
Q

87 Photosynthesis affects the concentrations of two gases in the atmosphere – carbon dioxide, and what other gas?

A

oxygen

88
Q

88 Give the name of some of the earliest photosynthetic microorganisms.

A

cyanobacteria

89
Q

89 Certain gases in the atmosphere keep the Earth warm. What is this effect called?

A

greenhouse effect

90
Q

90 Give the name of one of the most common greenhouse gases.

A

carbon dioxide, methane, water vapour

91
Q

91 Name three greenhouse gases.

A

methane, carbon dioxide, water vapour, CFCs and many others

92
Q

92 Energy is transferred from the Sun by what?

A

infrared/electromagnetic) radiation/waves/light

93
Q

93 The warm Earth emits what type of electromagnetic waves?

A

infrared

94
Q

94 In an atmosphere containing greenhouse gases, what happens to some of the infrared waves that the Earth emits?

A

absorbed and re-emitted in all directions

95
Q

95 Why do modern thermometers give better quality evidence than those from the 18th century?

A

thermometers are now more accurate/have a better resolution

96
Q

96 What word beginning with c describes the way in which two variables appear to be linked because they show similar patterns of change?

A

correlation

97
Q

97 What term is used to describe the changes to average weather conditions around the world?

A

climate change

98
Q

98 Evidence for carbon dioxide variations over the last 800 000 years comes from Antarctica. In what form is this evidence?

A

ice cores

99
Q

99 What type of human activity has mainly increased the level of greenhouse gases since 1750?

A

burning fossil fuels

100
Q

100 The acidity of the oceans is increasing due to more carbon dioxide dissolving in the water. What is this doing to the pH of the oceans?

A

decreasing it/making it more acidic

101
Q

What is a hydrocarbon?

A

A compound that is made up of hydrogen and carbon only

102
Q

What is crude oil?

A

A mixture of different length hydrocarbons

103
Q

How do we seperate out the mixture of crude oil?

A

Fractional distillation

104
Q

During fractional distillation, cruide oil is heated until…

A

it is a gas

105
Q

Where does crude oil go once it has become a gas?

A

It goes into a condensing column

106
Q

Long chain hydrocarbons which don’t evaporate become…

A

residue

107
Q

The residue that is left during fractional distillation of crude oil because it doesn’t evaporate is…

A

bitumen

108
Q

What is bitumen used for?

A

Making roads

109
Q

It is very hot/cold at the bottom of the condensing column

A

hot

110
Q

As we move up the condensing tower, the temperature increases/decreases

A

decreases

111
Q

At different temperatures in a condensing column…

A

different length hydrocarbons come off

112
Q

Gases can be produced at the top/bottom of the condensing column

A

Top

113
Q

Gasoline and naptha are produced near the top/middle/bottom of a condensing tower

A

Top

114
Q

Kerosene is produced in the top/middle/bottom of a condensing tower

A

Middle

115
Q

Diesel and fuel oil are produced near the top/middle/bottom of a condensing tower

A

Bottom

116
Q

Short hydrocarbons come off at the top/bottom of a condensing tower

A

Top

117
Q

Long hydrocarbons come off at the top/bottom of a condensing tower

A

Bottom

118
Q

Things at the top of a condensing column are highly/not very flammable

A

highly

119
Q

Things at the bottom of a condensing column are highly/not very flammable

A

Not very

120
Q

Things at the bottom of a condensing column are very/not viscous

A

very

121
Q

Things at the top of a condensing column are very/not viscous

A

not

122
Q

True/False: Long hydrocarbons that come out of fractional distillation aren’t always the most useful

A

True

123
Q

From fractional distillation we get lots/few long hydrocarbons which are/aren’t very useful

A

lots, aren’t

124
Q

From fractional distillation we get lots/few short hydrocarbons which are/aren’t very useful

A

few, are

125
Q

How do we crack long hydrocarbons?

A

Heat and a catalyst

126
Q

What does cracking long hydrocarbons produce?

A

Alkenes and short alkanes

127
Q

Complete combustion of a hydrocarbon involves lots of…

A

oxygen

128
Q

Complete combustion of a hydrocarbon involves lots of oxygen, which is the _______ ____ flame on a bunsen burner

A

roaring blue

129
Q

What is the word equation for complete combustion?

A

Hydrocarbon + oxygen -> water + carbon dioxide

130
Q

What is incomplete combustion?

A

When there is not enough oxygen

131
Q

What colour flame on a bunsen burner is incomplete combustion?

A

Orange

132
Q

Incomplete combustion is more problematic because…

A

it produces carbon monoxide, which is highly toxic, and carbon

133
Q

What is the word equation for incomplete combustion?

A

Hydrocarbon + oxygen -> water + carbon dioxide + carbon monoxide + carbon

134
Q

What are the 3 main greenhouse gases?

A

Carbon dioxide, water vapour and methane

135
Q

Which greenhouse gas has the largest impact on the environment?

A

Carbon dioxide

136
Q

The bonds in carbon dioxide are really good at absorbing…

A

infrared/heat radiation

137
Q

Carbon dioxide absorbing infrared radiation means that it becomes trapped in our atmosphere and therefore…

A

warms the planet

138
Q

What does the warming of the planet as a result of infrared radiation being trapped in our atmosphere mean?

A

When heat and light energy from the sun comes to the earth it is usually reflected back by the earth and would normally go straight out into space, however it is being trapped by greenhouse gases and therefore staying in our atmosphere and heating it up

139
Q

We can see a gradual increase/decrease in the levels of carbon dioxide over time

A

Increase

140
Q

The levels of carbon dioxide have picked up speed/slowed down in recent years

A

picked up speed

141
Q

True/False: There is one thing that humans do which is the reason that the levels of carbon dioxide are increasing

A

False, there are lots of things which humans do that increase the levels of carbon dioxide

142
Q

True/False: Global warming means that everywhere is getting hotter

A

False, not everywhere is getting hotter

143
Q

What impact is global warming having on deserts and farmland?

A

They are drying out completely

144
Q

What impact is global warming having on ice poles?

A

The are melting

145
Q

Why is the fact that ice poles are melting as a result of global warming bad for polar bears?

A

They live on these blocks of ice and hunt in the water - then jump on the ice when they need a rest. Because the ice is melting, there is nowhere for polar bears to rest and therefore lots are drowning

146
Q

Ice caps melting leads to increased/decreased levels of flooding in other places

A

Increased

147
Q

Why does the melting of ice caps result in flooding in some areas?

A

The sea levels are rising

148
Q

If sea levels continue to rise then…

A

certain places, especially areas on the coast, will end up underwater

149
Q

Whilst Australia are having their hottest Christmases ever, the UK are having their…

A

coldest Christmases ever and seeing unpresidented levels of snow

150
Q

True/False: Climate change only effects people

A

False, it effects animals and plants aswell

151
Q

As temperature changes, top of mountains which perhaps used to be under snow is now available for…

A

Habitation by new animals and plants

152
Q

If you have a house on top of a mountain which you know is protected from certain types of animals because you know it is too cold or warm for them there, the changing climate could mean…

A

That this is not the same anymore as with the changing climate animals are moving up and down slopes as their habitats are changing

153
Q

Why do animals’ habitats change?

A

As temperature changes and as the location of their food source changes

154
Q

What is your carbon footprint?

A

How much carbon your daily activities contribute to the atmosphere

155
Q

What kind of things impact a person’s carbon footprint?

A

Whether you drive or walk to a destination, whether you eat food that is grown locally instead of food that has travelled a long distance, etc

156
Q

Give 2 examples of human activities that contribute to the production of carbon dioxide

A

Any 2 from burning fossil fuels for use as electricity, deforestation - cutting down trees so that the trees can’t take up carbon dioxide from the atmosphere anymore and our reliance on petrol cars

157
Q

The predictions for the levels of carbon dioxide in the atmosphere is that…

A

they are just going to increase

158
Q

The predictions for global warming in coming years is…

A

It is just going to increase

159
Q

How can we stop the levels of carbon dioxide and global warming increasing?

A

If we as a population decide to do something about it

160
Q

Sulfur dioxide is one of the _____ pollutants

A

major

161
Q

What happens when sulfur dioxide goes up into the atmosphere?

A

It dissolves in the clouds and comes back down as acid rain

162
Q

When sulfur dioxide goes up into the atmosphere, what does it come back down as?

A

Acid rain

163
Q

Acid rain has an effect on a small/wide range of things

A

wide

164
Q

True/False: Animals are immune to acid rain

A

False, acid rain will hurt animals that come into contact with it

165
Q

What will happen to fish and plants in a lake/ocean/pond if a it becomes too acidic?

A

They will start to die

166
Q

True/False: Acid rain can kill plants

A

True

167
Q

True/False: Acid rain will destroy limestone statues as they will dissolve in the acid rain

A

True

168
Q

What are the effects of too much carbon in the air?

A

It will lead to large levels of smog and global dimming

169
Q

Where is smog and global dimming as a result of too much carbon in the air often prevelant?

A

Developing countries

170
Q

True/False: Water vapour contributes to the warming of the planet

A

True

171
Q

True/False: Carbon dioxide is not toxic

A

False, it is toxic

172
Q

True/False: Nitrogen oxides contribute to acid rain and help prevent smog

A

False, they contribute to smog and acid rain

173
Q

The air we breathe is made up of one gas/lots of different gases

A

lots of different gases

174
Q

The air we breathe is predominantly ________ gas

A

nitrogen

175
Q

What percentage of the air we breathe is oxygen?

A

21

176
Q

True/False: There is a large number of other gases in the air besides oxygen and nitrogen, including a small amount of carbon dioxide

A

True

177
Q

What was the early atmosphere mainly formed from?

A

Things coming out of volcanoes

178
Q

True/False: In the earth’s early atmosphere there was a small amount of ammonia

A

False, there was a large amount of ammonia

179
Q

True/False: In the earth’s early atmosphere there was methane

A

True

180
Q

In the earth’s early atmosphere there was/wasn’t any water vapour in the air

A

was

181
Q

True/False: There was no carbon dioxide in the air in the earth’s early atmosphere

A

False, there was some

182
Q

Why would the earth’s early atmosphere not be a nice place to be?

A

Ammonia smells like old baby nappies and methane smells like farts

183
Q

Why did the levels of water vapour in the earth’s early atmosphere decrease?

A

It rained and therefore made the oceans

184
Q

Give 2 reasons why levels of carbon dioxide in the earth’s early atmosphere decreased?

A

Any 2 from it dissolved in oceans, turned into fossils and photosynthesis started to take place

185
Q

With the evolution of green plants, oxygen started to increase/decrease

A

increase

186
Q

Why did the levels of oxygen in earth’s early atmosphere start to increase?

A

Photosynthesis started to take place

187
Q
A

GCSE Combined Chemistry (Edexcel) (5 decks)

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