Chemistry Paper 2 Flashcards
(197 cards)
1
Q
What is the formula for calculating the rate of reaction in terms of reactant?
A
Mean rate of reaction = quantity of reactant used / time taken
2
Q
What is the formula for calculating the rate of reaction in terms of product?
A
Mean rate of reaction = quantity of product formed / time taken
3
Q
State the two units of measurement that reactants and products can be measured in.
A
By mass in grams or volume in cm3
4
Q
What are the two possible units for rate of reaction?
A
g/s or cm³/s (where s is seconds)
5
Q
What are the three possible units for rate of reaction?
A
g/s or cm³/s or mol/s (where s is seconds)
6
Q
Susan carried out an experiment. 15g of product is made over 5 seconds. Calculate the rate of reaction.
A
15/5 = 3 g/s
7
Q
Abdullah reacts magnesium with hydrochloric acid. The mass of the reactants decreases by 12.3 g over 3 seconds. Calculate the rate of reaction.
A
4.1 g/s
8
Q
Natalie mixes two solutions together to produce a gas. 70cm3 of gas is produced in 3.5 seconds. Calculate the rate of reaction.
A
20 cm3/s
9
Q
1 mol of gas is produced in 80 seconds when a solid is reacted with an acid. Calculate the rate of reaction.
A
0.0125 mol/s
10
Q
State the 5 factors that affect the rates of chemical reactions.
A
1) Concentration of reactants in solutions
2) Pressure of reacting gases
3) The surface area of solid reactants
4) Temperature
5) Presence of catalysts
11
Q
How does increasing the pressure of reacting gases affect the rate of reaction?
A
It increases.
12
Q
How does decreasing the pressure of reacting gases affect the rate of reaction?
A
It decreases.
13
Q
How does increasing the concentration of reactants in solution affect the rate of reaction?
A
It increases.
14
Q
How does decreasing the concentration of reactants in solution affect the rate of reaction?
A
It decreases.
15
Q
How does increasing temperature affect the rate of reaction?
A
It increases
16
Q
How does decreasing temperature affect the rate of reaction?
A
It decreases.
17
Q
How does increasing the surface area of solid reactants affect the rate of reaction?
A
It increases
18
Q
How does decreasing the surface area of solid reactants affect the rate of reaction?
A
It decreases.
19
Q
How does the presence of a catalyst affect the rate of reaction?
A
It increases
20
Q
State the two conditions that need to be met in order for particles to react.
A
1) Particles must collide
2) They must collide with sufficient energy
21
Q
Define activation energy.
A
The minimum amount of energy that particles must have to react.
22
Q
Predict and explain the affect of increasing concentration on the rate of chemical reaction.
A
Reactions occur when particles collide with sufficient energy.
Increasing concentration means there are more particles in the same volume.
So there are more frequent collisions.
The rate of reaction increases.
23
Q
Predict and explain the affect of increasing surface area on the rate of chemical reaction.
A
Reactions occur when particles collide with sufficient energy.
Increasing surface area exposes more particles.
So there are more frequent collisions.
The rate of reaction increases.
24
Q
Predict and explain the affect of increasing temperature on the rate of chemical reaction.
A
Reactions occur when particles collide with sufficient energy.
When the temperature increases particles move faster with more energy.
There are more frequent collisions meeting the activation energy.
Rate of reaction increases.
25
Predict and explain the affect of decreasing pressure on the rate of chemical reaction.
Reactions occur when particles collide with sufficient energy.
Decreasing the pressure means less gas particles in the same volume.
So there are less frequent collisions.
The rate of reaction decreases.
26
What is a catalyst?
Something which changes the rate of a reaction but is not used up in that reaction
27
How do catalysts speed up reactions?
They provide a different route for the reaction to take place which has a lower activation energy.
28
The same catalyst can be used for many different reactions. True or false?
False.
29
What are enzymes?
Biological catalysts.
30
Many industrial processes use catalysts. Suggest why.
Catalysts provide a different route for the reaction to take place which has a lower activation energy.
Less energy is required.
Saves money.
31
How are reversible reactions different to reactions that go to completion?
In reversible reactions the product of the reaction can react to produce the original reactants.
32
By looking at a word or symbol equation, how can you determine if a reaction is a reversible reaction?
A reversible reaction will have a reversible arrow sign. ⇌
33
If a reaction is exothermic in the forward direction what will it be in the reverse direction?
Endothermic
34
Two reactants require 30kJ to turn into products. What energy transfer is involved when the products turn into reactants?
30kJ is released
35
What is equilibrium?
The point in a reversible reaction when the forward and reverse reactions are occurring at the same rate in a closed system.
36
How is the amount of reactant changing at equilibrium?
It is not changing
37
How is the amount of product changing at equilibrium?
It is not changing
38
What condition must be met in order for equilibrium to be established for a reversible reaction?
The reaction must take place in a closed system.
39
What is Le Chatelier's principle?
When a reaction at equilibrium is changed, it will seek to counteract that change
40
N2(g) + 3H2(g) ⇌ 2NH3(g)
The above reaction occurs in a reaction mixture. Ammonia is removed from the reaction mixture. Explain the effect on the position of equilibrium.
Moves to the right hand side to produce ammonia.
| To counteract the change.
41
2HCl(g) ⇌ H2(g) + Cl2(g)
The above reaction takes place in a reaction mixture. Hydrochloric acid is added to the reaction mixture. Explain the affect on the position of equilibrium.
Moves to the right hand side to produce hydrogen and chlorine.
To counteract the change.
42
2HCl(g) ⇌ H2(g) + Cl2(g)
The forward reaction is endothermic. Predict the effect of increasing the temperature on the amount of chlorine gas produced at equilibrium. Explain your answer using Le Chatelier's Principle.
1) Amount of chlorine gas increases
2) Because system shifts to counteract the change
3) Because shifts to endothermic direction / shifts to take in energy
43
C2H4(g) + H2O(g) -> C2H5OH(g) ΔH = −45 kJ per mole
How would increasing the temperature change the YIELD of ethanol at equilibrium? Give a reason for your answer.
1) Increasing the temperature would lower the yield / equilibrium position moves to the left
2) Since the backwards reaction is endothermic / the forward reaction is exothermic
44
How does temperature affect the position of equilibrium?
Raising the energy of the system will shift it towards the endothermic reaction. Lowering it shifts it to the exothermic reaction.
45
C2H4(g) + H2O(g) -> C2H5OH(g) ΔH = −45 kJ per mole
How would increasing the pressure change the YIELD of ethanol at equilibrium? Give a reason for your answer.
1) Increasing the pressure would increase the yield / position of equilibrium moves to the right
2) Because the position moves in the direction of the lower number of moles of gas
46
2HCl(g) ⇌ H2(g) + Cl2(g)
| Explain the effect of increasing the pressure on this equilibrium.
No change because there is an equal number of gas molecules on each side of the equation.
47
N2(g) + 3H2(g) ⇌ 2NH3(g)
The above reaction occurs in a reaction mixture. A low pressure is used in this reaction. Explain the effect on the yield of ammonia.
Decreases yield, because there are more moles/molecules of gas on the left hand side.
48
How does pressure affect the position of equilibrium?
Moves the position of equilibrium towards the side with less molecules.
49
What type of resource is crude oil?
It is a non-renewable finite resource.
50
What is crude oil made up of?
The remains of ancient biomass consisting mainly of plankton.
51
What is a finite resource?
One that will run out
52
Why is crude oil a finite resource?
Because we are using it faster than it is being produced.
53
What is a hydrocarbon?
A compound made of atoms of carbon and hydrogen only
54
Name the first four alkanes
Methane, ethane, propane, butane
55
What is the general formula for alkanes?
CnH2n+2
56
Most of the compounds in crude oil are what type of molecule?
Hydrocarbons
57
What is the formula of methane?
CH4
58
What is the formula for propane?
C3H8
59
Name the alkane with the formula C2H6
Ethane
60
Name the alkane with the formula C4H10
Butane
61
What is fractional distillation?
A process used to separate mixtures of substances with different boiling points
62
What are the steps involved in fractional distillation?
Crude oil is heated and vaporised.
Gas molecules rise up the fractionating column.
They condense at different points in the column as they have different boiling points.
Molecules with similar boiling points are separated within the same fraction.
63
The products of the fractional distillation of crude oil can be used for two main things. What are they?
1) Used as fuel
| 2) Feedstock for the petrochemical industry
64
Name four materials that are produced by the petrochemical industry.
Solvents, lubricants, polymers and detergents
65
Name five fuels we obtain from crude oil
Petrol, diesel, kerosene, heavy fuel oil and liquefied petroleum gases
66
What is a fuel?
A substance which when reacted with oxygen releases a large amount of energy
67
Complete the word equation: hydrocarbon + oxygen ->
hydrocarbon + oxygen -> carbon dioxide + water
68
During combustion, the carbon and hydrogen in hydrocarbons are reduced. True or False?
False, they are oxidised.
69
When does incomplete combustion occur?
When there is not enough oxygen present
70
How does boiling point change with the length of an alkane?
The longer the alkane, the higher its boiling point
71
How does viscosity change with the length of an alkane?
The longer the alkane, the more viscous (the thicker) it is
72
How does flammability change with the length of an alkane?
The longer the alkane, the less flammable it is
73
Write a balanced equation for the combustion of methane CH4
CH4 + 2O2 -> CO2 + 2H2O
74
What is cracking?
The process of breaking down a long hydrocarbon into smaller hydrocarbons
75
What are the products of cracking?
Short alkanes and alkenes
76
Why is cracking important?
Because it produces smaller hydrocarbons of which there is a greater demand because they are more useful than larger hydrocarbons.
77
How are alkenes different to alkanes?
Alkenes are more reactive than alkanes
78
How do you test for the presence of an alkene?
React with bromine water. Positive test will show colour change from bright orange to colourless.
79
What are alkenes used to produce?
Polymers.
80
Describe the process of steam cracking.
The hydrocarbon is heated until it vaporises.
It is mixed with steam.
The mixture is heated to a very high temperature.
The long chain cracks to produce a smaller alkane and an alkene.
81
Describe the process of catalytic cracking.
The hydrocarbon is heated until it vaporises.
It is passed over a hot powered aluminium oxide catalyst.
The long chain cracks to produce a smaller alkane and an alkene.
82
Complete the equation to show the cracking of a large hydrocarbon. C23H48 -> C12H26 + ______
C23H48 -> C12H26 + C11H22
83
Complete the equation to show the cracking of a large hydrocarbon. _________ -> C11H24 + C8H16
C19H40 -> C11H24 + C8H16
84
In chemistry what is a "pure" substance?
A substance made of a single element or compound, not mixed with any other substances.
85
Pure elements and compounds melt and boil at…...
specific temperatures
86
How can pure substances be distinguished from impure ones?
By their melting/boiling points
87
Describe the melting and boiling points of impure substances
They change state at a range of temperatures
88
Water boils at 100oC. When salt is added to water how does the boiling point of water change?
It increases and occurs over a range of temperatures.
89
Ice melts at 0oC. When salt is added to ice how does the melting point change?
It lowers and occurs over a range of temperatures.
90
In everyday language what is a "pure" substance?
A substance that has nothing added to it, so it is in its natural state.
91
Considering how the word pure is used in everyday language, give an example of a pure substance.
Honey, milk etc…
92
What is a formulation?
A mixture designed as a useful product
93
Give three examples of formulations
fuels, cleaning agents, paints, medicines, alloys, fertilisers and foods.
94
How are formulations made?
By mixing the components in in carefully measured quantities to ensure that the product ahs the required properties.
95
What is chromatography?
A process to separate the constituents of a mixture
96
In paper chromatography, what is the difference between the mobile phase and stationary phase?
Paper is stationary, solvent (usually water or ethanol) is mobile
97
How can chromatography show the difference between pure and impure substances?
Pure substances will only produce a single spot.
98
State the equation to calculate the Rf value.
Rf = distance moved by substance / distance moved by solvent
99
A student carried out a chromatography practical. The solvent moved 110mm from the baseline. A yellow pigment moved 46mm from the baseline. Calculate the Rf value of the yellow pigment. Give your answer to 2 dp
0.42
100
How would chromatography show that some food colourings are mixtures?
There would be more than 1 dot in a vertical line.
101
From a chromatogram, how can you determine which substance is most soluble in the solvent used?
That substance will have travelled up the furthest and be closest to the solvent front.
102
Why are substances in a mixtures separated out at different heights on a chromatogram?
Because they have different levels of attraction to the paper, and different solubility in the solvent
103
Why is lid/watch glass placed over the beaker when carrying out a chromatography practical?
To stop the solvent from evaporating.
104
What should you draw the baseline with and why?
A pencil so it doesn't dissolve in the solvent.
105
Different compounds have the same Rf values in different solvents. True or false?
False.
106
How can hydrogen be tested for?
Makes a squeaky pop when a lighted splint is placed in it
107
How can oxygen be tested for?
Relights a glowing splint
108
How can carbon dioxide be tested for?
Bubble through limewater, turns it milky (cloudy)
109
How can chlorine be tested for?
Bleaches damp litmus paper white
110
For how long have the proportions of different gases in the atmosphere been the same as they are today?
200 million years
111
What percentage of gas in the atmosphere is nitrogen?
Roughly 80%
112
What percentage of gas in the atmosphere is oxygen?
Roughly 20%
113
Other than nitrogen and oxygen, what other gases are present in the atmosphere?
Carbon dioxide, water vapour and noble gases.
114
Why have theories about what was in the Earth's early atmosphere changed and developed over time?
Because of the timescale of it being 4.6 billion years ago. No one was alive then.
115
Fill in the blanks. One theory about the Earth's early atmosphere states that during the first billion years of the Earth's existence there was intense ___________ activity that released ________ that formed the early atmosphere.
volcanic, gases
116
What gases do some scientists think were present in the Earth's early atmosphere?
Carbon dioxide, water vapour, methane, ammonia and nitrogen
117
How do some scientists think carbonate precipitates formed the sediments on the sea bed?
Carbon dioxide dissolved in the water of the oceans and through a series of chemical reactions produced carbonate precipitates that formed sediments on the sea bed.
118
How do some scientists think the early oceans were formed?
The Earth cooled and some of the water vapour in the Earth's atmosphere condensed to form the oceans.
119
Which planets of today do some scientists think the Earth's early atmosphere was like?
Mars and Venus
120
State the word equation for photosynthesis.
Carbon dioxide + water -> glucose + oxygen (light above the arrow)
121
State the balance symbol equation for photosynthesis.
6CO2 + 6H2O -> C6H12O6 + 6O2
122
How did the amount of oxygen in the early atmosphere increase?
Algae first produced oxygen 2.7 billion years ago, they photosynthesised, increasing the amount of oxygen in the atmosphere.
123
Apart from algae, which other organism can photosynthesise?
Green plants.
124
When algae and plants photosynthesise, the decrease the amount of a certain gas in the atmosphere. Name this gas.
Carbon dioxide.
125
During the evolution of the Earth's early atmosphere, the amount of carbon dioxide decreased. State the two main ways in which it decreased.
1) Algae and plants photosynthesising
| 2) By the formation of sedimentary rocks and fossil fuels that contain carbon.
126
Why are greenhouse gases essential to support life on Earth?
They maintain temperatures on Earth high enough to support life.
127
State three greenhouse gases.
Water vapour, methane and carbon dioxide.
128
Describe the greenhouse effect.
Short wavelength radiation from the sun passes through the atmosphere to the Earth's surface, the Earth heats up and then cools emitting longer wavelength radiation. The greenhouse gas molecules absorb and re-radiate this in all directions including back down to Earth, heating the Earth.
129
State two human activities that have increased the amounts of carbon dioxide in the Earth's atmosphere.
Deforestation
| Burning fossil fuels
130
State two human activities that have increased the amounts of methane in the Earth's atmosphere.
Agriculture - raising more cattle
| Creating more waste - more landfill sites and agricultural waste
131
Why are scientists concerned about the human activities that cause an increase in the amount of greenhouse gases in the atmosphere?
Scientists believe it will cause the temperature of the Earth's atmosphere to increase at the surface and that this will result in global climate change.
132
The evidence for climate change has been peer-reviewed. Why is this important?
So that you know the information is reliable. Helps prevent false claims.
133
Why is it difficult to fully understand the Earth's climate?
Because the Earth's climate is a complex system that is very difficult to model.
134
It is very difficult for scientists to model the Earth's climate. What problems can this lead to?
This can lead to simplified models, speculation and opinions presented in the media that may be based on only parts of the evidence and which may be biased.
135
Complete the sentence: "An increase in average __________ ____________ is a major cause of climate ___________."
Global temperature, change
136
Describe the effect of global climate on rainfall patterns.
Changes in rainfall patterns may cause some regions to get too much or too little water.
137
Describe the effect of global climate on sea levels.
Increase in global temperatures could lead to polar ice caps melting - causing a rise in sea levels, increasing flooding in coastal areas and coastal erosion.
138
Describe the effect of global climate on storms.
The frequency and severity of storms may increase.
139
Describe the effect of global climate on water availability.
Changes in temperature and the amount of water available in a habitat may affect wild species leading to differences in their distribution.
140
Define carbon footprint.
The total amount of carbon dioxide and other greenhouse gases emitted over the full life cycle of a product, service or event.
141
Complete the sentence: "The carbon footprint can be ____________ by reducing ________________ of carbon ______________ and methane."
Reduced, emission, dioxide
142
What alternative fuels could be used instead of fossil fuels to reduce carbon footprints?
Renewable energy resources or nuclear energy.
143
Describe two ways in which governments can help reduce carbon footprints.
1) Governments could tax companies or individuals based on the amount of greenhouse gases they emit.
2) Government could put caps on emissions of all greenhouse gases that companies make - then sell licences for emissions up to that cap.
144
How can carbon capture help reduce carbon footprints?
Carbon dioxide produced can be 'captured' and stored deep underground in cracks in the rock such as old oil wells.
145
Why might companies review the processes they use to reduce carbon footprints?
They may review them to explore more efficient processes that cut waste reduce greenhouse gas emissions.
146
State two reasons why reducing greenhouse gas emissions may be limited.
1) A lot of work needs to be done developing alternative technologies that result in less emissions - costly.
2) Governments may be worried that making changes will have a negative impact on economic growth.
3) It is difficult to make international agreements on reducing greenhouse gas emissions when not everyone is on board.
147
State a major source of atmospheric pollutants.
The combustion of fuels.
148
Complete the sentence: "Most fuels, including coal, contain _______ and/or hydrogen and may also contain some ____________."
Carbon, sulphur
149
How can sulphur dioxide be produced?
From the combustion of fossil fuels containing sulphur impurities.
150
How can nitrogen oxides be produced?
By the reaction of nitrogen and oxygen in air, caused by the heat of burning in the internal combustion engines of cars. (Very high temperatures)
151
Explain how soot (carbon particulates) can form.
The incomplete combustion of fuel because not enough oxygen is present.
152
Write a balanced equation for the production of nitrogen dioxide from nitrogen and oxygen.
N2 + 2O2 --> 2NO2
153
Sulphur dioxide is dissolved in water. What colour is universal indicator in a solution of sulphur dioxide?
Red/Orange/Yellow
154
The incomplete combustion of fossil fuels produces carbon monoxide. What problems can carbon monoxide cause?
Carbon monoxide binds to haemoglobin which stops oxygen from binding.
This means less oxygen is able to be transported around the body.
A lack of oxygen can lead to fainting, a coma or even death.
155
The incomplete combustion of fossil fuels can produce carbon soot (particulates). What problems do these particulates cause?
1) If inhaled they can cause damage to the lungs leading to respiratory problems.
2) They are also bad for the environment and can cause global dimming.
156
Sulphur dioxide and oxides of nitrogen can cause harm to the environment. Explain how.
These gases can mix with clouds to form dilute sulphuric and nitric acid. This falls as acid rain and can kill plants and damage buildings and statues.
157
Sulphur dioxide and oxides of nitrogen can cause harm to humans, why?
They can cause respiratory problems if breathed in.
158
Give one advantage of reducing emissions of oxides of nitrogen.
Less acid rain or fewer respiratory problems in humans.
159
True or false - Sulphur dioxide causes global dimming.
False.
160
Why is carbon monoxide very difficult to detect?
It is a colourless, odourless, tasteless gas. It is very hard to detect.
161
Where do humans obtain natural resources from?
The Earth, sea and air.
162
Name the four things human use the Earth's resources to provide:
Warmth, shelter, food and transport.
163
Complete the sentence: "Natural resources, supplemented by ________________, provide food, timber, clothing and fuels.
Agriculture
164
Define sustainable development.
Development that meets the needs of current generations without compromising the ability of future generations to meet their own needs.
165
What does synthetic mean?
Man made.
166
What is meant by a renewable resource?
A resource that is being made as fast as it is used up.
167
What is meant by a non-renewable resource?
A finite resource, that is being used up faster than it is being made.
168
Give 2 examples of finite resources.
Fossil fuels (coal, oil and gas) and nuclear fuels (plutonium and uranium).
169
State 2 examples of natural products that are supplemented or replace by agricultural and synthetic products.
1) Rubber can be replace by synthetic polymers.
| 2) Fertilisers can be used to produce a high yield of crops.
170
Define potable water.
Water that is safe to drink.
171
Explain why potable water is not pure.
Because it contains small amounts of dissolved substances.
172
Which two factors will determine the way in which potable water is produced?
1) The available supply of water
| 2) Local conditions
173
Define freshwater.
Naturally occurring water with a small amount of dissolved substances.
174
Describe how potable water is produced in the UK.
1) Choosing an appropriate source of fresh water e.g. lake
2) Pass the water through filter beds to remove large solid bits
3) Sterilise the water - this can include using chlorine, ozone or ultraviolet light.
175
If supplied of freshwater are limited, what other method can be used to produced potable water?
Desalination of salty water or sea water.
176
State the two methods used to produce potable water from seawater.
1) Distillation
| 2) By processes that use membranes such as reverse osmosis.
177
Describe the difference in energy demand of producing potable water from sea water instead of fresh water.
The two methods that produce potable water from sea water require a large amount of energy.
178
Describe three places where waste water can come from.
1) Sewage from domestic sources
2) Agricultural systems
3) Industrial processes
179
Why must waste water be treated before being released back into the environment?
So that the environment isn't polluted - waste water can cause harm to wildlife.
180
State the 4 steps involved in sewage treatment.
1) Screening and grit removal
2) Sedimentation to produce sewage sludge and effluent
3) Anaerobic digestion of sewage sludge
4) Aerobic biological treatment of effluent
181
State the two products of the anaerobic digestion of sewage sludge.
Natural gas and fertiliser.
182
What additional treatments may be required for waste water containing toxic substances?
1) Adding chemicals to precipitate metals
2) UV radiation
3) Using membranes
183
Is copper a finite or renewable resource?
Finite.
184
Describe how copper can be extracted from low-grade ore by phytomining.
1) Plants are grown in soil that contains copper
2) Copper gradually builds up in the leaves
3) The plants can are harvested, dried and burned in a furnace.
4) The ash contains soluble copper compounds that can be extracted by electrolysis or displacement with a more reactive metal e.g. scrap iron.
185
Describe how copper can be extracted from low-grade ore by bioleaching.
1) Bacteria are used to convert copper compounds into soluble copper compounds, separating the copper from the ore in the process
2) The leachate (the solution produced by the process) contains copper ions, which can be extracted by electrolysis or displacement with a more reactive metal e.g. scrap iron.
186
Why are Life Cycle Assessments carried out for?
To look at the environmental impact at every stage of a product's life.
187
State the four stages of a products life.
1) Extracting and processing raw materials
2) Manufacturing and packaging
3) Use and operation during its lifetime
4) Disposal at the end of its life, including transport and distribution at each stage
188
Describe how extracting and processing raw materials can have an impact on the environment.
1) Extracting raw material can damage the local environment e.g. mining.
2) Raw materials often need processing which requires large amounts of energy - burning fossil fuels produces greenhouse gases.
189
Describe how manufacturing and packaging of an item can have an impact on the environment.
1) Often requires a large amount of energy - burning fossil fuels produces greenhouse gases.
2) Some processes at can produce waste products that need to be disposed of. These can pollute the environment and cause damage to plants and wildlife.
190
Describe how using a product can have an impact on the environment.
1) The product may run on fuel. Burning fossil fuels produces greenhouse gases.
2) Fertilisers can leach into streams causing damage to ecosystems.
191
Describe why LCAs are not a purely objective process.
Allocating numbers to pollutants effects is difficult and would require a judgement based on the person's values. This means LCAs can be biased.
192
State two ways in which we can reduce the use of limited resources.
1) Reuse products
| 2) Recycle materials
193
Why might the extraction and processing of resources be unsustainable?
Because the processes require large amounts of energy - obtained from finite resources.
194
State one way in which chemists can reduce the energy demand industrial processes.
By using catalysts.
195
How is glass recycled?
Glass bottle are crushed and melted to make different glass products.
196
How are metals recycled?
Metals can are melted and recast or reformed into different products.
197
The amount of separation required for recycling depends on the material and the properties required for the final product. Give an example of this.
Waste steel and iron can be kept together as they can both be added to iron in a blast furnace to reduce the amount of iron ore required.
