Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

C12- ALKANES > 12.4- COMBUSTION OF ALKANES > Flashcards

12.4- COMBUSTION OF ALKANES Flashcards

(86 cards)

Start Studying
1
Q

How reactive are alkanes?

A

quite unreactive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What do alkanes not react with?

A

acids, bases, oxidising agents or reducing agents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What do alkanes burn and react with under suitable conditions?

A

burn and will react with halogens under suitable conditions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

How well do shorter chain alkanes burn in a plentiful supply of oxygen?

A

burn completely

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is produced when shorter chain alkanes are burnt in a plentiful supply of oxygen?

A

carbon dioxide and water

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What does combustion reactions give out?

A

give out heat

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the enthalpies of combustion like?

A

large negative enthalpies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is greater when there’s more carbon present in combustion?

A

greater the heat output

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Why are alkanes with more carbon important in fuels?

A

when combusted they have a great heat output

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are fuels?

A

substances that release heat energy when they undergo combustion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What do fuels store a large amount of in a small amount of weight?

A

store a large amount of energy for a small amount of weight

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Examples of alkane fuels? (5)

A 
methane
propane 
butane 
petrol
paraffin
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What fuel is methane used for?

A

natural or North Sea gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What fuel is propane used for?

A

camping gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What fuel is butane used for?

A

calor gas

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What types of hydrocarbons make up petrol?

A

mixture of hydrocarbons of approximate chain length C8

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What does a limited supply of oxygen in combustion cause the production of?

A

poisonous gas carbon monoxide

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What sort of combustion is it when carbon monoxide is formed?

A

incomplete combustion

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is produced when even less oxygen is provided in combustion?

A

carbon (soot)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Example of carbon (soot) being formed from incomplete combustion in lab?

A

when Bunsen burner used with a closed air hole, flame is yellow and black sooty deposit appears on apparatus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

When does incomplete combustion often happen?

A

often happens when with longer chain hydrocarbons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Why does incomplete combustion often happen with longer chain hydrocarbons?

A

they need more oxygen to burn compared with shorter chains

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What do all hydrocarbon-based fuels derived from crude oil may produce when they’re burnt?

A

polluting products

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Different types of polluting products made from when hydrocarbon-based fuels derived from crude oil are burnt? (7)

A 
carbon monoxide 
nitrogen oxides 
sulfur dioxide 
carbon particles 
unburnt hydrocarbons 
carbon dioxide 
water vapour
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
What is carbon monoxide?
poisonous gas produced by incomplete combustion
26
Examples of nitrogen oxides?
NO, NO2, N2O4
27
How are nitrogen oxides formed?
produced when there is enough energy for nitrogen and oxygen in the air to combine
28
Equation of how nitrogen and oxygen combine to form nitrogen oxides?
N2 (g) + O2 (g) = 2NO (g)
29
Example of where does nitrogen and oxygen combine to form nitrogen oxides?
petrol engine at high temperatures present, when sparks ignite fuel
30
What may the nitrogen oxides from petrol engine react with to form?
oxides may react with ester vapour and oxygen in the air to form nitric acid
31
As the nitrogen oxides from petrol engines eventually produce nitric acid, what are they contributors of?
contributors of acid rain and photochemical smog
32
What is sulphur dioxide a contributor of?
acid rain
33
Where is sulphur dioxide produced from?
produced from sulphur-containing impurities present in crude oil
34
How does sulphur dioxide produce acid rain?
this oxide combines with water vapour and oxygen in the air to form sulphuric acid
35
What are carbon particles called?
particulates
36
What can particulates exacerbate and cause?
exacerbate asthma and cause cancer
37
What type of gas is carbon dioxide?
greenhouse gas
38
What is always produced when hydrocarbons are burnt?
carbon dioxide
39
What is the increasing levels of carbon dioxide in the atmosphere causing?
cause of an increase in the Earth's temperature and consequent climate change
40
What type of gas is water vapour?
greenhouse gas
41
How do a large number of power stations generate electricity?
by burning fossil fuels such as coals or natural gas
42
What do coals and natural gas contain?
sulphur compounds
43
What is a product of combustion of coals and natural gases as they contain sulphur compounds?
sulphur dioxide, SO2
44
What does sulphur dioxide cause?
acid rain
45
How does sulphur dioxide cause acid rain?
by combining with oxygen and water in the atmosphere to form sulphuric acid
46
Equation for how sulphur dioxide reacts with oxygen and water to form sulphuric acid?
S02 (g) + 1/2O2 (g) + H20 (l) = H2SO4 (l)
47
What is the gases given out by power stations called?
flue gas
48
What is the process of removing the sulphur dioxide from flue gas called?
flue gas desulphurisation
49
What is one method of flue gas desulphurisation?
slurry of calcium oxide (lime) + water is sprayed into the flue gas which reacts with calcium oxide + water to form calcium sulphite, which can be further oxidised to calcium sulphate
50
What is calcium sulphate also called?
gypsum
51
What is the overall reaction of flue gas desulphurisation into gypsum?
CaO (s) + 2H20 (l) + S02 (g) + 1/2O2 = CaSO4.2H20(s)
52
What is gypsum used to make?
builder' plaster and plasterboard
53
What is an alternative method of flue gas desulphurisation?
use calcium carbonate (limestone) rather than calcium oxide
54
What is the equation for flue gas desulphurisation using calcium carbonate?
CaCO3 (s) + 1/2O2 (g) + SO2 (g) = CaSO4 (s) + CO2 (g)
55
What does the internal combustion produce most of?
most of the pollutants listed previously
56
What is removed from petrol to make it less of a problem?
sulphur removed from petrol so sulphur dioxide has become less of a problem
57
What are all new cars with petrol engines now equipped with?
catalytic converters in their exhaust systems
58
What do the catalytic converters in the exhaust systems of petrol engine cars do?
reduce output of carbon monoxide, nitrogen oxides and unburnt hydrocarbons in the exhaust gas mixture
59
What is the catalytic converter?
honeycomb made of a ceramic material coated with platinum and rhodium metals
60
What are the catalysts on a catalytic converters?
platinum and rhodium
61
What does the honeycomb structure of catalytic converters provide?
provide enormous surface area, so little of these expensive metals (platinum + rhodium) go a long way
62
What happens when the polluting gases pass over the catalyst of the catalytic converter?
react with each other to form less harmful products
63
Equation for how carbon monoxide reacts with nitrogen oxide over catalytic converter?
2CO (g) + 2NO (g) = N2 (g) + 2CO2 (g)
64
Word equation for how hydrocarbons react with nitrogen oxide over catalytic converter?
hydrocarbons + nitrogen oxide = nitrogen + carbon dioxide + water
65
Where does the reactions take place on the catalytic converter?
on the surface of the catalyst, on the layer of platinum and rhodium metals
66
What is the temperature like inside a greenhouse?
greenhouses become very warm inside
67
Why does it become very warm inside a greenhouse?
because visible rays from sun pass through the glass
68
What happens to the visible rays that pass through the glass of a greenhouse?
rather than escaping, their energy is absorbed by everything inside the greenhouse and re-radiated as infrared energy (heat)
69
What is the wavelength of infrared energy in comparison to visible rays?
infrared energy has a longer wavelength
70
Can infrared energy pass out of the glass of greenhouses?
no
71
How does carbon dioxide behave in terms of a greenhouse?
like glass
72
How does carbon dioxide act like glass of a greenhouse?
it traps infrared radiation so that the Earth's atmosphere heats up
73
Why is carbon dioxide and other greenhouse gases important?
without it the Earth would be too cold to sustain life
74
What are examples of other greenhouse gases other than carbon dioxide? (2)
water vapour and methane
75
Are methane and water vapour more effective than carbon dioxide?
yes
76
How has the levels of methane and water vapour in the atmosphere changed over the years?
not been much change
77
What has happened since the industrial revolution?
fossil fuels have been used to fuel industrial plants and the level of carbon dioxide has been rising
78
As the levels of CO2 has been rising, what has also been increasing?
Earth's temperature
79
What is the most abundant greenhouse gas?
water vapour
80
How does the concentration of water vapour change in the atmosphere?
tends to stay the same
81
Where does the concentration of water vapour in the atmosphere not stay the same?
near waterfalls
82
Why does the concentration of water vapour in the atmosphere tend to stay the same?
because of the equilibrium that exists between water vapour and liquid water
83
What happens to water vapour when there's an increase in temperature?
will be more water vapour in the air and so more greenhouse warming
84
What can the increase in water vapour in the air be offset by?
offset by greater cloud formation and clouds reflect solar radiation
85
Why are many people concerned about activities such as airline flights?
they produce large amounts of carbon dioxide
86
What are activities that produce no carbon dioxide emission overall refereed to as?
carbon neutral

C12- ALKANES (5 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions