Chemistry paper 2 Flashcards
1
Q
How do you measure the rate of a reaction?
A
- loss of reactants
- production of products
2
Q
Give two ways to measure the quantity of reactant or product:
A
- Mass
- Gass produced
- Colour change
- PH
3
Q
What are the units for measuring rate of reaction?
A
amount measured/time —> gas produced = volume/time
4
Q
Give three ways to measure the rate of reaction:
A
- colour change
- mass lost
- gas produced
5
Q
How can a change in temperature affect the rate of reaction?
A
higher temperature = faster
6
Q
How does a change in pressure affect the rate of reaction?
A
high pressure = faster
7
Q
How does a change in concentration affect the rate of reaction?
A
higher concentration = faster
8
Q
How does a change in the surface area affect the rate of reaction?
A
large = faster
9
Q
What is a catalyst?
A
Speeds up the rate of reaction but aren’t used up
10
Q
How can a catalyst affect the rate of reaction?
A
Speed it up
11
Q
What happens to ammonium chloride upon cooling and heating?
A
heat - decomposition
= ammonia + hydrogen chloride
12
Q
What happens to copper sulphate in addition or removal of water?
A
removal of water means colour change blue to white
13
Q
What is Le Chatelier’s principle?
A
Whatever you do to a reaction the reaction will do the opposite
14
Q
Define hydrocarbon:
A
A compound that only has hydrogen and carbon in it
15
Q
What is crude oil made up from?
A
A mixture of different length hydrocarbons
16
Q
What are the general formulae for alkanes?
A
CnH2n+2
17
Q
Methane:
A
CH4
18
Q
Ethane:
A
C2H6
19
Q
Propane:
A
C3H8
20
Q
Butane:
A
C4H10
21
Q
Why do we need to separate crude oil into fractions?
A
Cause each fraction has different properties used for different things
22
Q
How does B.P. change with chain length?
A
Long = high BP
23
Q
How does viscosity change with chain length?
A
Long = Very viscous
24
Q
How does flammability change with chain length?
A
Long = low flammability
25
Write the word equation for complete combustion:
Hydrocarbon + oxygen -> Carbon-dioxide + water
26
Why do we need to crack long hydrocarbons?
Long ones aren't very useful but we have lots of them
27
How do we test for alkenes?
Bromine water test -> alkenes = orange to colourless
28
Define mixture:
Some elements or compounds that may or may not be chemically be bonded together
29
Define formulation:
Preparing something
30
Define melting point:
Exact temperature at which an object melts
31
How can the melting point be used to determine if a compound is pure or not?
It should all melt at the same temperature
32
How can chromatography be used to determine if a compound is pure or not?
It will separate out everything and if pure it will all be in one spot
33
How do you calculate RF values?
How far a spot has moved
34
What is the test for hydrogen gas?
Squeaky pop
35
What is the test for oxygen gas?
Relighting a glowing splint
36
What is the test for carbon-dioxide?
Turns limewater cloudy
37
What is the test for chlorine gas?
bleaches damp litmus paper
38
How much oxygen is in the atmosphere?
21%
39
How much CO2 is in the atmosphere?
0.04%
40
How much nitrogen is in the air?
78%
41
How was the early atmosphere different to today?
More CO2 +CH4 -> less O2 + N2
42
What led to an increase in oxygen in the atmosphere?
photosynthesis
43
What led to an increase in nitrogen in the atmosphere?
break down of ammonia + methane
44
2 things that decreased the amount of CO2:
- Dissolved in oceans
| - Got locked in rocks
45
What are three greenhouse gases?
C02, CH4,H2O
46
How do greenhouse gases interact with radiation?
Causes bonds to vibrate as they absorb and release of heat
47
Greenhouse gases effect on climate?
changes climates - traps heat etc.
48
2 activities that lead to a rise in greenhouse gases?
- burning fossil fuels
| - deforestation
49
Prediction of future temperature levels?
massive increase
50
Define the term carbon footprint:
amount of carbon given out based on daily activities
51
What are the major sources of atmospheric pollution?
Power stations + cars
52
What effect does carbon-dioxide have on the atmosphere?
It traps in radiation - causing things to become warmer
53
What effect does sulfur dioxide have on the atmosphere?
Will lead to water vapour
54
What effect does water vapour have on the atmosphere?
greenhouse gas - trap radiation
55
What effect does carbon monoxide have on the atmosphere?
greenhouse gas - trap radiation
56
What effect does nitrogen oxides have on the atmosphere?
greenhouse gas - more efficient - better at trapping heat
57
What effect do carbon particles have on the atmosphere?
Global dimming - similar to soot
58
What effect does pollution have on humans?
Air pollution -> health risk
59
What effect does pollution have on plants?
A change in PH of water or nutrients
60
What effect does pollution have on animals?
long-term - Animals have to evolve to survive, e.g. moths - short-term acid rain
61
What different ways can humans use earth's resources?
plants - food +animals
| mining - resources and minerals
62
Give three resources we get from the earth:
- water
- fossil fuels
- rocks
63
Define finite resources:
Something that will run out
64
Define renewable resource:
Never going to run out
65
How do you produce portable water?
Filtration + boiling
66
How do you sterilise water?
Heat to kill + filter
67
How do you desalinate water?
evaporate and condense the water
68
Why are new methods of material extraction necessary?
because materials aren't as accessible as they previously used to be
69
What is bioleaching?
Uses bacteria to extract copper from low yield ores
70
What is phytomining?
Uses plants to extract copper from low yield ores - broccoli
71
How do we access the impact of an object?
production, use, recyclability
72
How do we analyse a life cycle assessment?
energy requirement and environmental impact
73
How can we reduce the number of resources used?
We can reuse things/recycle things
74
What is rusting?
When iron mixes with water to produce iron oxide
75
How can we prevent corrosion?
By removing one of the things that cause rusting e.g. water or oxygen or by covering the object to prevent these from coming in contact with it
76
What is the structure of an alloy?
A distorted structure with no layers
77
How does a structure of an alloy relate to its properties?
Distorted structure means no sliding between layer meaning it is very hard
78
What is the composition of most of the glass we use?
silicon dioxide
79
What are clay ceramics?
Made from clay and sand which is baked and end up being very hard
80
How does the structure of polymers relate to their properties?
strong crosslinks - do not melt - thermosetting
| weak intermolecular forces - melt when heated - thermosoftening
81
What is the Haber process used for?
Production of ammonia
82
In the Haber process, where do nitrogen and hydrogen come from?
The air
83
What conditions are needed for the Haber process?
Iron catalyst, 450º C, 200 atmospheres
84
What is the general formula for alkenes?
CnH2n
85
What does unsaturated mean?
double bonds
86
What is the word equation for incomplete combustion?
Hydrocarbon + Oxygen ---> CO2, H20, CO and carbon particles
87
Difference between complete and incomplete combustion?
```
complete = lots of O2
incomplete = not a lot of 02
```
88
Alkene + Halogen?
Bromine water -> colour change
89
Alkene + Water?
Take water and produces alcohol
90
Alkene + Hydrogen?
Hydrogonation or hardening
91
What is the functional group for alcohol?
O-H-
92
What is the main use of alcohol?
drinking
93
What happens when sodium reacts with alcohol?
violent reaction
94
What happens when alcohol reacts with oxygen?
burn
95
What happens when alcohol reacts with an oxidising agent?
Carboxylic acids
96
What are conditions needed for fermentation?
yeast, glucose, warm
97
What are uses for carboxylic acids?
Vinegar
98
Happens when a carboxylic acid reacts with a carbonate?
Gas will be CO2
99
Happens when a carboxylic acid reacts with water?
Lose a hydrogen ion
100
Happens when a carboxylic acid reacts with alcohol?
ester + water
101
Define monomer:
A small bit
102
Define polymer:
Lots of small bits joined together
103
Describe polymerisation:
Joining together of small bits
104
What is condensation polymerisation?
Polymerisation with a small molecule where water is usually released
105
What is the structure of DNA?
Double Helix
106
How does DNA relate to amino acids?
we have 3 DNA bases which make an amino acid
107
What is the colour flame test for lithium?
red
108
What is the colour flame test for sodium?
brick red/orange
109
What is the colour flame test for potassium?
lilac
110
What is the colour flame test for calcium?
yellowy red
111
What is the colour flame test for copper?
blue/green
112
What happens when you react with sodium hydroxide with aluminium?
White precipitate + more will eventually dissolve
113
What happens when you react with sodium hydroxide with calcium?
White precipitate
114
What happens when you react with sodium hydroxide with magnesium?
White precipitate
115
What happens when you react with sodium hydroxide with copper (II)?
Blue precipitate
116
What happens when you react with sodium hydroxide with iron (II)?
Blue/green/grey precipitate
117
What happens when you react with sodium hydroxide with iron (III)?
Red/Brown precipitate
118
What is the test for carbonate ions?
mix with the acid = release of CO2
119
What is the test for halide ions?
Add silver nitrate = Chloride -> white - Bromide -> Cream ppt - Iodide -> yellow ppt
120
What is the test for sulfate ions?
Add Barium chloride = White ppt
