8) Fuels & Earth Science Flashcards
(95 cards)
1
Q
What type of resource is crude oil?
A
Non-renewable
2
Q
Where is crude oil found?
A
In rocks
3
Q
What is crude oil used to produce?
A
Fuels and other important chemicals
4
Q
What are hydrocarbons?
A
Molecules made up of only hydrogen and carbon atoms
5
Q
What changes the properties of hydrocarbons?
A
Their differences in size
6
Q
What are most of the compounds in crude oil?
A
Hydrocarbons
7
Q
What is crude oil a mixture of?
A
Lots of different compounds that are not chemically combined
8
Q
What is crude oil made from?
A
Fossilised plankton
9
Q
What are groups of hydrocarbons with similar numbers of carbon atoms called?
A
Fractions
10
Q
What is the process of separating crude oil into groups of hydrocarbons with similar numbers of carbon atoms?
A
Fractional distillation
11
Q
What are hydrocarbons with lots of carbon atoms called?
A
Long-chain hydrocarbons
12
Q
What are hydrocarbons with few carbon atoms called?
A
Short-chain hydrocarbons
13
Q
What are the stages of fractional distillation?
A
Evaporation
Condensation
Collection
14
Q
What can fractions be used to make?
A
Solvents
Detergents
Lubricants
15
Q
What is the gases fraction used for?
A
Domestic heating and cooking
16
Q
What is the petrol fraction used for?
A
Fuel for cars
17
Q
What is the ketrosene fraction used for?
A
Fuel for aircrafts
18
Q
What is the diesel oil fraction used for?
A
Fuel for trains and some cars
19
Q
What is the fuel oil fraction used for?
A
Fuel for large ships and power stations
20
Q
What is the bitumen fraction used for?
A
Surfacing roads and roofs
21
Q
What are the crude oil fractions in order?
A
Gases Petrol Kerosene Diesel oil Fuel oil Bitumen
22
Q
What differs with the size of hydrocarbons?
A
Melting points
23
Q
What is a homologous series?
A
A series of compounds with the same general formula
24
Q
How do the physical and chemical properties change in a homologous series:?
A
Similar chemical properties
Changing physical properties
25
What do the molecular formulas of neighbouring compounds in a homologous series differ by?
A CH2 unit
26
How do the properties of a larger hydrocarbon change?
Higher boiling point
Less flammable
Higher viscosity
27
What is the process that breaks down long-chain hydrocarbons into shorter chain molecules?
Cracking
28
What type of chemical reaction is cracking?
Thermal decomposition
29
What are the two ways of cracking?
Catalytic cracking
| Steam cracking
30
What is catalytic cracking?
Vapourised heavy hydrocarbons are passed over the top of a heated alkene
31
What is produced in cracking?
Alkanes and alkenes
| e.g. hexane --> butane + ethene
32
What is steam cracking?
Vapourised heavy hydrocarbons are mixed with steam in a high temperature environment
33
What is cracking?
Breaking down long-chain hydrocarbons into shorter more useful molecules
34
What do the equations for combustion of hydrocarbons depend on?
The amount of available oxygen
35
What does the combustion of hydrocarbons when there is good oxygen supply involve?
Energy release
| Creation of carbon dioxide and water
36
What does incomplete combustion of hydrocarbons produce?
Carbon monoxide
| Soot
37
Why can soot cause problems?
It can build up in appliances such as cars
38
What is produced when alkanes are burned without enough oxygen?
Carbon monoxide
39
What are properties of carbon monoxide?
Colourless
Toxic
Odourless
40
What happens when hydrocarbons burn in a confined space?
High temperatures cause nitrogen and oxygen to react
41
What does the reaction of nitrogen and oxygen form?
Toxic nitrogen oxides
42
What impurity is found in all fossil fuels?
Sulfur
43
What happens when sulfur burns?
It oxidises
44
What does burning sulfur produce?
Toxic gas sulfur dioxide
45
What can happen if sulfur dioxide is inhaled?
Respiratory problems
46
What is formed from the reaction of sulfur dioxide and water?
Sulfuric acid
47
What is a major component of acid rain?
Sulfur dioxide
48
What can be used as an alternative to petrol as fuels in cars?
Hydrogen fuel cells
49
What are advantages of using hydrogen over petrol?
Only waste product is water
No greenhouse gases emited
More energy per gram
50
What are disadvantages of using hydrogen over petrol?
Hydrogen must be stored at a high pressure
Hydrogen gas is explosive
Lack of places to refuel
51
What is the chemical reaction of burning hydrocarbons with a lack of oxygen?
2C + O2 --> 2CO
52
How long ago was the Earth formed?
4.6 billion years ago
53
What gas dominated the early atmosphere?
Carbon dioxide
54
What was littered across Earth's surface for the first billion years?
Volcanoes
55
What did frequent eruptions of volcanoes form?
```
Release of carbon dioxide
Nitrogen
Water vapour
Methane
Ammonia
```
56
Why did the oceans form?
Water vapour condensed
57
What did the formation of oceans cause?
A significant reduction in atmosphere carbon dioxide levels
58
What was produced by reactions between dissolved carbon dioxide and seawater?
Carbonate precipitates
59
What was deposited as sediment?
Carbonate precipitates
60
What increased the atmospheric concentration of oxygen?
Photosynthesis
61
What does photosynthesis produce?
Glucose
| Oxygen
62
What was the first photosynthetic organism?
Algae
63
When did the first organism begin to photosynthesise?
2.7 billion years ago
64
What did a higher oxygen threshold allow to form?
Complex life forms such as animals
65
What 3 factors caused atmospheric carbon dioxide to decrease?
Marine animals
Oceans
Photosynthesis
66
How did marine life cause atmospheric carbon dioxide to reduce?
They removed carbonates from the ocean to build shells and skeletons
67
What is the test for oxygen?
Insert a glowing splint into a test tube containing a gas
| If gas is oxygen, splint will relight
68
What is the process of the greenhouse effect?
1) Sun emits short wavelength infrared radiation
2) Earth absorbs portion of radiation but longer wavelength is reflected back into the atmosphere
3) Greenhouse gases can't absorb short wavelength radiation but can sbsorb reflected radiation
4) Gases re-radiate this as heat energy and some heads back towards Earth
5) This increases Earth's surface temnperature
69
What human activites cause the atmospheric concentrations of gases to increase?
Burning fossil fuels
Agriculture
Deforestation
Landfill sites
70
How do landfill sites increase greenhouse gases?
Mounds of waste decompose
| Decomposition releases methane
71
How does agriculture increase greenhouse gases?
Farm animals relsease methane during digestion
72
How does deforestation increase greenhouse gases?
Global rate of photosynthesis decreases
| Less carbon dioxide removed from atmposhere
73
How does burning fossil fuels increase greenhouse gases?
Releases carbon as carbon dioxide
| This carbon had been stored away for millions of years
74
What are 3 greenhouse gases?
Carbon dioxide
Methane
Water vapour
75
Why is it difficult to create accurate climate change models?
The global climate system is very complicated
76
How is misinformation spread on climate change?
Published in media
| Some people have motives to downplay climate change
77
What are sources of misinformation on climate change?
Biased opinions
| Overly simplistic models
78
What are potential consequences of climate change?
```
Melting polar ice caps
Meteorological events
Changes in water availability
Changes in precipitation
Food shortages
```
79
What does melting polar ice caps cause?
Rising sea leves
Some species will be less successful hunters
Coastal erosion
80
What could changes in water availability cause?
How species are distributed
81
What changes to precipitation could climate change cause?
Quantity
Timing
Distribution
82
How much of the Earth's atmosphere is oxygen?
21%
83
How much of the Earth's atmosphere is nitrogen?
78%
84
What gases make up Earth's atmosphere?
```
Nitrogen
Oxygen
Argon
Carbon dioxide
Methane
Water vapour
Neon
```
85
What factors make a good fuel?
```
Cheap
Low boiling point
High volatility
Ignties easily
Low emissions
```
86
What is volatility?
How easily a compound evaporates
87
How do you test if a substance is pure?
Compare to a known pure fuel
| Pure substance boils over a very small temperature range
88
What do plants use carbon to produce?
Sugars
89
Where are compounds with the lowest boiling point collected in fractional distillation?
The top of the column
90
What is the volatility of compounds with a low boiling point?
High
91
What are fossil fuels formed from?
Organic material that has been buried and compressed
92
What is coal formed from?
Plant deposits
93
What reaction occurs when fossil fuels are burnt?
Combustion reaction
94
What is one of the products of burning fossil fuels?
Carbon dioxide
95
What reacts with oxygen during the burning of fossil fuels?
Organic molecules formed by photosynthesis
