GCSE Workbook The Earth's Resources
GCSE Chemistry 8462. GCSE exams June 2018 onwards. Version 1.0 21 April 2016
4.10.1 Using the Earth's resources and obtaining potable water 4.10.1.1 Using the Earth's resources and sustainable development Content
Key opportunities for skills development
Humans use the Earth’s resources to provide warmth, shelter, food and transport. Natural resources, supplemented by agriculture, provide food, timber, clothing and fuels. Finite resources from the Earth, oceans and atmosphere are processed to provide energy and materials. Chemistry plays an important role in improving agricultural and industrial processes to provide new products and in sustainable development, which is development that meets the needs of current generations without compromising the ability of future generations to meet their own needs. Students should be able to: • state examples of natural products that are supplemented or replaced by agricultural and synthetic products • distinguish between finite and renewable resources given appropriate information. Students should be able to: • extract and interpret information about resources from charts, graphs and tables
WS 3.2
• use orders of magnitude to evaluate the significance of data.
MS 2h
MS 2c, 4a
Translate information between graphical and numeric form.
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4.10.1.2 Potable water Content
Key opportunities for skills development
Water of appropriate quality is essential for life. For humans, drinking water should have sufficiently low levels of dissolved salts and microbes. Water that is safe to drink is called potable water. Potable water is not pure water in the chemical sense because it contains dissolved substances. The methods used to produce potable water depend on available supplies of water and local conditions. In the United Kingdom (UK), rain provides water with low levels of dissolved substances (fresh water) that collects in the ground and in lakes and rivers, and most potable water is produced by: • choosing an appropriate source of fresh water • passing the water through filter beds • sterilising. Sterilising agents used for potable water include chlorine, ozone or ultraviolet light. If supplies of fresh water are limited, desalination of salty water or sea water may be required. Desalination can be done by distillation or by processes that use membranes such as reverse osmosis. These processes require large amounts of energy. Students should be able to: • distinguish between potable water and pure water • describe the differences in treatment of ground water and salty water • give reasons for the steps used to produce potable water. Required practical 8: analysis and purification of water samples from different sources, including pH, dissolved solids and distillation. AT skills covered by this practical activity: 2, 3 and 4. This practical activity also provides opportunities to develop WS and MS. Details of all skills are given in Key opportunities and skills development (page 107).
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GCSE Chemistry 8462. GCSE exams June 2018 onwards. Version 1.0 21 April 2016
4.10.1.3 Waste water treatment Content
Key opportunities for skills development
Urban lifestyles and industrial processes produce large amounts of waste water that require treatment before being released into the environment. Sewage and agricultural waste water require removal of organic matter and harmful microbes. Industrial waste water may require removal of organic matter and harmful chemicals. Sewage treatment includes: • • • •
screening and grit removal sedimentation to produce sewage sludge and effluent anaerobic digestion of sewage sludge aerobic biological treatment of effluent.
Students should be able to comment on the relative ease of obtaining potable water from waste, ground and salt water.
4.10.1.4 Alternative methods of extracting metals (HT only) Content
Key opportunities for skills development
The Earth’s resources of metal ores are limited. Copper ores are becoming scarce and new ways of extracting copper from low-grade ores include phytomining, and bioleaching. These methods avoid traditional mining methods of digging, moving and disposing of large amounts of rock. Phytomining uses plants to absorb metal compounds. The plants are harvested and then burned to produce ash that contains metal compounds. Bioleaching uses bacteria to produce leachate solutions that contain metal compounds. The metal compounds can be processed to obtain the metal. For example, copper can be obtained from solutions of copper compounds by displacement using scrap iron or by electrolysis. Students should be able to evaluate alternative biological methods of metal extraction, given appropriate information.
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4.10.2 Life cycle assessment and recycling 4.10.2.1 Life cycle assessment Content
Key opportunities for skills development
Life cycle assessments (LCAs) are carried out to assess the environmental impact of products in each of these stages:
WS 1.3, 4, 5
• • • •
extracting and processing raw materials manufacturing and packaging use and operation during its lifetime disposal at the end of its useful life, including transport and distribution at each stage.
LCAs should be done as a comparison of the impact on the environment of the stages in the life of a product, and only quantified where data is readily available for energy, water, resources and wastes.
Use of water, resources, energy sources and production of some wastes can be fairly easily quantified. Allocating numerical values to Interpret LCAs of materials pollutant effects is less straightforward and requires value or products given judgements, so LCA is not a purely objective process. appropriate information. Selective or abbreviated LCAs can be devised to evaluate a product but these can be misused to reach pre-determined conclusions, eg MS 1a in support of claims for advertising purposes. Recognise and use expressions in decimal Students should be able to carry out simple comparative LCAs for form. shopping bags made from plastic and paper. MS 1c Use ratios, fractions and percentages. MS 1d Make estimates of the results of simple calculations. MS 2a
Use an appropriate number of significant figures. MS 4a Translate information between graphical and numeric form.
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GCSE Chemistry 8462. GCSE exams June 2018 onwards. Version 1.0 21 April 2016
4.10.2.2 Ways of reducing the use of resources Content
Key opportunities for skills development
The reduction in use, reuse and recycling of materials by end users reduces the use of limited resources, use of energy sources, waste and environmental impacts. Metals, glass, building materials, clay ceramics and most plastics are produced from limited raw materials. Much of the energy for the processes comes from limited resources. Obtaining raw materials from the Earth by quarrying and mining causes environmental impacts. Some products, such as glass bottles, can be reused. Glass bottles can be crushed and melted to make different glass products. Other products cannot be reused and so are recycled for a different use. Metals can be recycled by melting and recasting or reforming into different products. The amount of separation required for recycling depends on the material and the properties required of the final product. For example, some scrap steel can be added to iron from a blast furnace to reduce the amount of iron that needs to be extracted from iron ore. Students should be able to evaluate ways of reducing the use of limited resources, given appropriate information.
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Finite and Renewable resources We use the earth’s resources to live so that we can feed, stay warm and fuel transport. We have historically used ……………………….. products gathered from the environment and farming these has increased supply. Chemists have also developed ……………………………. alternatives. Natural resources Wool Cotton Silk Linseed oil Rubber
Use Clothes, carpets Clothes, textiles Clothes paint Tyres, washers
Wood
Construction
Synthetic alternative Acrylic fibre Polyester Nylon Acrylic resin Synthetic polymers like poly(butadiene) PVC, composites like MDF
Resources can be classified as either …………………… or Infinite. ………………………….. resources are those that are being used up at a faster rate than they can be replaced. Many chemical industries use natural resources to make new products. • …………………………………. from metal ores • Petrochemicals from …………………….... oil • Cement from …………………………………… …………………………….. resources are those that can be replaced at the same rate at which they are being used up. Finite resources will run out if they are continuously used. Wherever possible industries are moving towards renewable resources to improve ………………………………….
Sustainability: Developments that meet the needs of society now, without endangering the ability of future generations to meet their needs.
Sustainable Development “Sustainable development is development that meets the needs of the present, without compromising the ability of future generations to meet their own needs.” It seeks to ............................................... different and, often competing, needs against an awareness of the environmental, social and economic limitations we face as a society. It takes into consideration the environment and also making sure we have a strong, healthy and just society in existing and future communities. Humans use the Earth’s resources to provide .............................................................................................................for us. These naturally resources, supplemented by agriculture, provide us with ...................................................................... We need them in order for us to live. The earth’s finite resources are process to provide .................................................................. and materials that are used in every part of our lives. The earth’s renewable resources are ...................................................................... to do the same. Chemists are essential to improving agriculture, industrial processes to provide new products all in a ...................................................... way. Find case studies of innovative sustainable development ideas for each of these: Agriculture With an ever-growing population that requires a balanced nutritional diet, we are having to find new and more sustainable ways of providing ............................. for the world. What new practices have been introduced? Which are definitely not sustainable? Transport In a world of increased productivity and connectivity, new sustainable methods of .................................................. and moving about are required. What ideas do people have about keeping our ability to move people and goods without compromising the needs of future generations? Warmth Warmth is increasingly seen as a right, particularly in cold countries. How will we keep an ever increasing and spreading population ......................................... in a sustainable way? How can we sustainably warm (or cool) the homes of everybody? 8/26
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Water Water is the oil of the future as potable water gets increasingly ............................. and the population ............................... How will be make sure that everyone gets enough water to drink without fighting over it. What ways have people reintroduced so our water consumption is sustainable? Materials What materials are being developed or have been developed that will make our development more ........................................ without hindering technological advancement? Find some examples of ways we can use material sustainably or how they can be processed to get better use out of them. Biodiversity With more species being discovered than ever before but with biodiversity decreasing faster than before, what can we do to maintain sustainable biodiversity?
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Potable Water Water of appropriate quality is essential for life. For humans, drinking water should have sufficiently low levels of dissolved ............................... and ............................. Water that is safe to drink is called ....................................... water. Potable water is not pure water in the chemical sense as is still contains dissolved substances. The methods used to produce potable water depend on available supplies of water and local conditions. In the UK, rainwater has small amounts of dissolved substances that collect in the ground, lakes and rivers. Potable water is produced by a) choosing an appropriate source b) passing the water through filter beds c) sterilizing Sterilizing agents include ................................., ozone and ultra violet light.
If supplies of freshwater are limited, ................................... of salty water or seawater may be required. Desalination can be done by distillation or by processes that use membranes such as reverse ........................................ These processes use large amounts of energy.
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Waste Water Treatment Urban lifestyles and industrial processes produce large amounts of .......................................... In homes we produce wastewater from the toilet, the bath, the washing machine and dishwasher all of which have different ................................................. in them. Industry uses most of the water often for ............................................ or using as a solvent. These required treatment before being released into the sea or being recycled into the mains water network. Sewage and agricultural wastewater require removal of: • Organic matter • Harmful microbes Industrial waste water may require removal of: • Organic matter • Harmful chemicals Sewage treatment has four stages: 1. Screen and grit removal 2. Sedimentation to produce sewage sludge and effluent 3. Anaerobic digestion of sewage sludge 4. Aerobic biological treatment of effluent. Any solid material that is produced can be sold as ....................................... or sent to landfill depending on its type. .................................... is often generated from the process and can be sold also. The treated water is often only used in agriculture. Most of the time the water is not potable but can be used for most other purposes. High concentrations of pesticides, fertilizers or pharmaceuticals may still be in it and will not be removed unless they are identified before treatment.
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The process is long and complicated and stages need to be added to remove specific pollutants that are identified. This might be to remove high concentrations of nutrients to protect the waters from ................................................... or pathogens and ammonia near to freshwater fisheries. As a process of making water, taking it straight from an aquifer or borehole is much easier and cheaper.
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Water Treatment Schematic
Sewage Treatment Schematic
Extracting Metals from ores Extracting Copper from copper-rich ores Most copper is extracted from copper-rich ores. These are …………………….. and are in danger of running out. The two main methods use to obtain copper metal from its ore are: 1. Sulfuric acid is used to produce copper sulfate solution, from which copper is extracted by …………………………. or …………………………. by scrap iron.
2. …………………………….. of the copper ore to a high temperature with air to produce impure copper. Impure copper is purified by electrolysis too.
Metal ions are positive and always attracted to the negative electrode. This method gives very pure copper to make electrical wiring. Extracting Low grade copper ores For low grade ores (previously discarded waste material), the first two methods would be uneconomical. Two methods are used to extract the copper. 1. Bioleaching (using bacteria) …………………….. feed on the low-grade ores. By chemical and biological processes, a leachate (solution of copper ions) is extracted. Scrap iron or ……………………….. are used to extract the copper from the leachate which can then be further purified.
2. Phytomining (using plants) …………………………….. that can absorb copper ions are grown on the slag heap of previously discarded waste. The plants are then ………………….. and the copper extracted from the copper compounds found in the ash. Copper ions are ‘leached’ from the ash by sulfuric acid to make a solution called the Leachate. Displacement with scarp iron produces pure copper metal.
The purification of copper
Sludge – the impurities The diagram above shows how copper is purified. The copper anode is impure. When the power supply is switched on the copper 2+ metal atoms in the anode jump into solution. Meanwhile, those copper ions (Cu ) already in solution are attracted to the copper 2+ cathode (because they’re negative) and so copper metal forms. Since, Cu are turning into Cu atoms, they must have gained an electron. This is reduction. The half equation is !! !! + 2! ! → !"
An alternative method that is often employed is the displacement of copper from solution by the use of scrap metal. Iron is more reactive than copper.
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Life cycle assessment Life cycle assessments or LCAs are carried on any product that is produced to assess the ................................................ impact of that product in each of its life. 1. 2. 3. 4. 5. 6.
................................. Processing of raw ..................................... Manufacturing Distribution Use and operation during its lifetime ..................................... at the end of its useful life, including transport and distribution at each stage.
The Life Cycle Assessment is a ‘cradle-to-grave’ approach for assessing industrial systems. It is a tool used by companies when they are considering the economics and sustainability of a manufacturing process. It will help a company decide on what material to use and what product to produce. The goal of the life cycle is to: 1. Quantify or otherwise characterize all the inputs and outputs of a product’s life span 2. Specify the potential environmental impact of these material flows 3. Consider alternative approaches that change those impacts for the better.
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Reducing, Reusing & Recycling
The resources of the Earth are limited so it’s important that what we do now doesn’t make it difficult or impossible for future generations. Therefore we need to balance: 1. The need for .................................... development where the standard of living improves for everyone 2. Respect for the ............................................ and the resources it provides us
To try and so this we can try to eliminate the demand for something, then ................................. the amount required of the material, then ............................... it if possible, then ................................ and finally, if no other option is left, dispose in landfill or incineration.
..................................... is a very important way of trying to achieve this balance. Many resources are recyclable, but many are not. Recycling, saves valuable finite mineral .........................., it saves ....................., it reduces the waste disposal problem. It is less expensive than mining the ore and extracting the material at first in many cases. In order to recycle, all the material must be collected, transported and sorted, all of which has a financial and economic cost to it. Separating rubbish is often the main problem. Glass Glass is easily recycled. It can be melted and re-moulded to form new objects. This process requires less energy than that required in making it from its raw materials. However, the glass needs sorting into colours and transporting to a recycling plant. Metal It takes less energy to melt and re-mould metal than it does to make it new from its ores. Aluminium is particularly energy intensive to make and recycling it has a huge advantage. 8/26
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Copper ore is very rare now is a metal where most new copper products are made from recycled copper. Scarp iron is often put into the blast furnace again with new material. Many metals are alloys and so it can be very difficult to sort out all the metals for recycling. Paper Paper is broken up into small pieces, dissolved and then made into new sheets. This takes less energy than making it new from trees. However, paper can only be recycled a few times before the fibres become too short to be useable. Usually the recycled paper is not as good quality and can only be used for toilet paper or cardboard. Afterwards it can be used as a fuel or compost. Plastics Plastics are often cheaper to make new and many can’t be recycled easily. Each individual plastic has to be recycled in its own way. See the symbols on the container. Some will say widely recycled, some only in some areas and some not at all.
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Finite and renewable resources Humans use the Earth’s resources to provide warmth, shelter, food and transport. Natural resources, supplemented by agriculture, provide food, timber, clothing and fuels. Finite resources from the Earth, oceans and atmosphere are Natural Use Alternative resource synthetic product processed to provide energy and materials. If we are able to maintain the production of certain resources without them running out for a long time they are said to be sustainable. In the event that demand for resources cant be met, synthetic alternatives have been developed by chemists which are often cheaper, and can be produced rapidly to meet demand. However these often use much of the Earths finite resources. Meaning they will run out one day. You can classify natural resources as being finite or renewable.
Wool
Clothes, carpets
Cotton
Clothes, textiles Clothes Paint
Silk Linseed oil Rubber Wood
Tyres, washers Construction
Acrylic fibre, (polyacrylonitrile), poly(propene) Polyester Nylon Acrylic resin Various synthetic polymers such as poly(butadiene) PVC, Composites (MDF)
Finite resources are those that are being used up at a faster rate than they can be replaced. So if we carry on using them at our current rate they will eventually run out. Fossil fuels are examples of finite resources. Renewable resources are those that can be replaced at the same rate at which they are being used up. The crops that make biofuels are an example of a renewable resource. Finite resources The chemical industry uses natural resources as the raw materials to make new products. Consider the following examples • • • •
Metal ores used to extract metals Crude oil used to make polymers and petrochemicals Limestone to make cement and concrete Crude oil to make the petrol, diesel and kerosene we use for transport
Examples of renewable resources Wherever possible, industries are moving towards renewable resources to conserve finite resources and improve sustainability. Examples of renewable resources include plastics produced from ethanol that is made by fermenting glucose from sugar cane rather than using crude oil. Another example is using woodchips in power stations rather than traditional fossil fuels.
1. What is meant by a sustainable resource? 2. How has society coped with the growing demand for natural resources like wool and cotton when supply cannot meet demand? 3. What are the advantages and disadvantages with synthetic materials like PVC, Nylon and other polymers that scientists use? 4. What is the difference between a finite and renewable resource? Can you give an example of each.
5. Draw the following table in your book and put the following resources into the correct columns: Wood, oil, leather, solar power, natural gas, cotton, nuclear fuels, coal, metals, ethanol (from fermentation) Finite
Renewable
6. Is limestone a finite or renewable source? Explain how you know this 7. Look at the following graph. If production stays at the same rate, which are the most sustainable materials? Explain your answer 8. Imagine the rate of consumption of these materials increased what would you expect to happen
Extension
1. Look at the two graphs and explain what the graph shows. 2. As a rough estimate there is 1.5 x1016 metric tonnes of fossil carbon on Earth. In 2013 it was also estimated that 9.2 x109 metric tonnes of carbon were burned worldwide in that year. Assuming that the 2013 rate of carbon use was to continue, calculate an order of magnitude estimate of how long fossil carbon will last. 3. However there are only 5.5 x1012 metric tonnes of fossil fuels that can be used as a useful resource existing on Earth. Assuming an estimated rate of fossil fuel use is 1 x10 10 metric tonnes per year, calculate an order of magnitude estimation of the time left before the fossil fuel reserves run out.
1501WS GCSE Water 02 Š RWGrime
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THE CHEMISTRY OF WATER Water is the most abundant substance on the surface of our planet and is essential for all life. The water cycle Water in rivers, lakes and the oceans is evaporated by the heat of the Sun. The water vapour formed rises into the atmosphere and forms clouds. The clouds cool as they rise further and produce rain. This is known as the water cycle.
Uses of water Water is an important raw material and has many uses. It is used as a solvent and as a coolant. It is used in many industrial processes including the manufacture of sulphuric acid. Solubility of solids Many compounds dissolve in water while many other compounds react with water to produce acidic or alkaline solutions. The solubility of a solute in water, or any other solvent, is usually given in grams of solute per 100 grams of water (or solvent) at that temperature. The solubility of most solutes increases as the temperature increases. A saturated solution is one in which no more solute will dissolve at that temperature. When a hot saturated solution cools some of the solute will separate from the solution. Purification of drinking water Drinking water is treated by passing water through filter beds to remove solid particles and then chlorine is added to kill bacteria.
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1501WS
The use of artificial fertilisers results in many natural waters being contaminated with dissolved nitrate and ammonium ions. Dissolved nitrate ions can have harmful effects on babies and so the levels of nitrate are carefully monitored. 1)
Draw a simple version of the water cycle with labelled arrows linking the following boxes: water in seas, lakes, rivers; clouds; rain (3)
2)
Give three uses for water.
(3)
3) a) Define the following words: solute, solvent, solution, saturated
(4)
b) What happens to the solubility of solids as the temperature rises? (1) c) In what form is the solubility of a solid in water measured? 4)
(1)
Describe the two main steps in the purification of drinking water. (4)
5) a) Why might rivers become contaminated by ammonium and nitrate ions? b) What harmful effect can nitrate ions have in drinking water?
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(1)
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Potable water Questions 1. List ten impurities that you might find in river water
2. What is the difference between pure water and potable water?
3. List some sources of potable water.
4. In areas where potable water is scarce, what options are available to inhabitants?
5. In 1854, 50,000 people died of cholera in London. Dr John Snow did some scientific detective work to find the source of the disease. He marked the deaths from chlorea and the positions of the street pumps from which people obtained their water on a map of London. Dr Snow came to the conclusion that one of the pumps was supplying contaminated water. How did he work out which pump was contaminated?
6. The table shows the world consumption of water over the last 30 years. Year
World consumption of water (millions tonnes per day) 10.0 11.5 13.0 15.0 17.0 20.0
1960 1970 1975 1980 1985 1990
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c. Suggest reasons for the change
d. Predict water consumption by 2000.
7. What is the break down of water usage in the home? Use the internet to find out.
8. What can be done to improve the efficiency of water usage a. In the home?
b. In agriculture?
c. In industry?
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Waste Water Treatment Questions
1. What happens in the sedimentation tank at the waterworks?
2. What can be used to sterilize water for drinking?
3. What is a. Sewage
b. Sludge
4. At a sewage plant, describe what happens in: a. Aeration tank
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b. Digesters 5. Groups of settlers in North America always built their villages on river banks, and discharged their sewage into the river. How did the river dispose of the sewage? Why can this method of sewage disposal not be used for larger settlements?
6. British tissues makes toilet paper, paper towels, paper handkerchiefs etc. They use a lot of bleach on the paper, and this bleach is one of the chemicals that the firm has to dispose of. Can you suggest how the firm could reduce the problem of bleach disposal?
7. Why do some lakes develop a think layer of algal bloom? a. Why is algal bloom less likely to occur in a river?
b. What harm does algal bloom do to a lake the is used as: i. A reservoir
ii. A fishing lake
iii. A boating lake?
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Bioleaching factsheet and questions Bioleaching is the extraction of specific metals from their ores through the use of bacteria. They do this by producing leachate solutions that contain the metal compounds. A leachate is simply the solution we get when a liquid passes through an organism. It can therefore be used to extract copper from its ore in a relatively clean process. Bacteria are usually used in the process. Bioleaching is very economical as it is very simple. This makes it quite a cheap process. It is also environmentally friendly, unlike traditional methods of extracting copper, where several damaging gases such as carbon dioxide and sulfur dioxide are produced during smelting. Bioleaching can be used on ores that are poor in quality (otherwise known as low grade ores). This is important because high grade ores are limited in their availiablitly. The process does have some problems however. The process is very slow compared to smelting. There are also some toxic chemicals produced which are harmful to the environment. Also, the efficiency by which the bacteria convert the copper ore into copper metal is very low, so there is a lot of waste.
Questions Foundation 1. What is bioleaching? (2 marks) _______________________________ ___________________________________________________________ 2. Describe what the leachate is and how it is formed (including the type of organism involved)? (3 marks) ___________________________________________________________ ___________________________________________________________ Higher 3. Evaluate bioleaching. Give three advantages of bioleaching and three disadvantages of bioleaching. (6 marks) _________________________ ___________________________________________________________ ___________________________________________________________ ___________________________________________________________ ___________________________________________________________
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Mr Singh
Oxygen
4
O
O
O O
O
gas, CO2
of a waste
production
leads to
Burning
O
impacts
for extraction
Almost empty
Major environmental
High grade copper mine
Lots of energy needed
Looks bad
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5
Cu
2+
ions
Roots
O
2-
O
O
O O
O
2-
O O
O O
2+
Cu
O
Copper compound
O
Soil
Root
copper source
from low grade
Copper ions
Phytomining
with copper
reacting
Oxygen
the roots
absorbed by
ions are
The copper
surf
Soil
2
electrode
Positive
Electrolysis
6
Soil surface
3
Roots
Copper ions
compound
electrode
Negative
the copper
Ash containing
Phytomining worksheet Foundation level questions 1) Using box one in the flow chart found in the notes section, explain why we might need to usemarks): phytomining to obtain pure copper? (2 __________________________________________________________ ________________________________________________________________ ________________________________________________________________ 2) Describe where the copper used in the reaction in box 5 came from? Use boxes 2 and 3 to help you. (2 marks): ______________________________________________ ________________________________________________________________ ________________________________________________________________ 3) Identify the copper compound formed in box 5, and name the elements that have reacted to make it. (3 marks): Copper compound ____________________ Element 1____________ Element 2 ______________ 4) Describe the reaction in box 5 in terms of the charges of the ions involved and the type of bond that is formed (4 marks): ___________________________________ ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ 5) Using boxes 4 and 5, describe how the copper compound is formed. (3 marks) ________________________________________________________________ ________________________________________________________________ ________________________________________________________________ 6) Name the compound found in the ash shown in box 6 (1 mark): __________________ 7) The ash is filtered before electrolysis. Why? (1 mark) _______________________ ________________________________________________________________ 8/26
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Phytomining higher level questions 1) Explain how electrolysis is used to purify copper (8 marks): ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________
2) Describe and explain the process of phytomining (4 marks) ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________
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Product Development and the Environment Activity – Life Cycle Assessment Worksheet Product that you are assessing: ________________________________________________ Inventory analysis Step 1 Materials Acquisition: Each material in a product has its own life cycle of use and waste. List all the materials (metal, plastic) in your product. One point is assigned for each different material in the product. Type of Raw Material
Points 1 1 1 1 1
Total Points Step 2 Materials Processing: Most metals and plastics must be processed before they are in a useful form for manufacturing. Again, list the metals and plastics in your product. Assign one point for each material. Plastics or Metals in the Product
Points 1 1 1 1 1
Life Cycles: Lesson 1, Product Development and the Environment Activity – Life Cycle Assessment Worksheet 8/26
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Total Points
Step 3 Manufacturing: All of the processed materials in your product must be formed and shaped into something useful for the product (like a metal screw or a plastic lever). List the different parts and pieces of your product that have been manufactured here. Assign one point for each part. Different Parts and Pieces in the Product
Points
1
1
1
1
1
1
1
Total Points
Step 4 Packaging: How is your product packaged for sale? Mark the boxes that correspond to the packaging of your product here. Add of the total points for the packaging of your product. Packaging
Points
None
0
Paper or cardboard packaging only
5
Plastic packaging only
15
Plastic and cardboard packaging
10
Styrofoam or rubber packaging
15
Instructions sheets included separately in package
5
Total Points Step 5 Transportation: Once a product is packaged, it needs to be transported to somewhere else for storage or sale. Transportation by trucks, planes or boats require fuel for energy and contribute to air pollution. Mark the box if your product uses transportation in any way. List the total points for the transportation of your product Transportation
Points
Life Cycles: Lesson 1, Product Development and the Environment Activity – Life Cycle Assessment Worksheet 8/26
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Yes, by plane, truck, or boat
15
None
1
Total Points Step 6 Use of the Product: all products have an amount of time that they can be used and reused. Check the box below that describes how long your product can be used. Use of Product
Points
Product can be used once
15
Product can be used for 5 years
10
Product can be used for over 10 years
5
Total Points Step 7 Disposal: Once a product has been used, it can be disposed of or recycled. Check the box which describes your product below. Parts of the Product Made from Plastics or Metals
Points
Product must be thrown away
15
Some product materials can be recycled
5
All of the product and product materials can be recycled
0
Total Points Impact analysis Add up the points for your product to determine its overall impact on the environment: Total Points
How did the overall environmental impact of your product compare with another product in your class? ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ Life Cycles: Lesson 1, Product Development and the Environment Activity – Life Cycle Assessment Worksheet 8/26
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___________________________________________________________________________ ___________________________________________________________________________
Improvement analysis 1. What could you change in your product to improve its impact on the environment? Describe your improvements here. ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 2. Look at your Inventory Analysis above. Re-calculate your score if you were to use the improvements you just described. Did your score change? By how much? ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 3. What would you need to do to reduce the environmental impact of your product even more?
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___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ 4. There are several types of engineering life cycle assessments. Read the three descriptions below. Cradle-to-Grave: The full life cycle of a product from raw materials (cradle) to the disposal phase (grave). Cradle-to-Gate: A partial product life cycle assessment that investigates a product from raw materials (cradle) to the gate of the manufacturing facility (gate) before transportation to the consumer. Cradle-to-Cradle: A product life cycle assessment, where the end phase includes recycling of the product into a new product. The recycled product can be identical or different to the original product. Which description best fits your product? Why? ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________ ___________________________________________________________________________
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Ks4 Uses of products from crude oil
Q1.
The figure below shows two types of clothes hanger.
The table below gives information from a Life Cycle Assessment (LCA) comparing these two clothes hangers.
Steel Wire Hanger Raw materials Iron ore, air, coal, limestone Manufacturing process Coal is heated at 1000°C to make coke. Iron ore is heated with coke, limestone and air to 1600°C. This produces impure molten iron.
Plastic Hanger Crude oil Crude oil is heated to 350°C for fractional distillation. A fraction is cracked at 850°C to produce alkenes. Alkenes are polymerised at 150°C.
Use during its lifetime
Impure molten iron is converted to steel by adding oxygen at 1700°C. May corrode over time
Keep its shape
Disposal at end of its life
Bends out of shape easily Landfill, where it will corrode Can be recycled
Can be incinerated (burnt)
Does not corrode
Landfill/Not biodegradable
Difficult to recycle
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Use the information in the table on the other side to compare the advantages and disadvantages of both types of hanger. [6 marks] __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________ __________________________________________________________________________________
R E F L E C T I O N Teacher comment
A R E A
WWW
EBI How will I show improvement?
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Thinking creatively
1. Make a sculpture using only rubbish 2. How sustainable are you? Take an online test then write some reflective comments. 3. Agriculture is the largest consumer of potable water. What can be done to reduce it’s water use and make it more efficient? 4. Perform a life cycle assessment on a product you own. Suggest ways of reducing its impact on the environment then write a letter to the manufacturer. 5. What is not recylable? What alternatives are there to those materials? Why are they not being used at the moment? 6. Compose an ode to a material 7. Be a fertiliser company sales executive. Make a powerpoint selling the virtues of your NPK fertiliser explaining its benefits and why the farmers should buy your fertiliser. 8/26
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Taking it further Our use of resources is a very topical debate. Awareness of the environmental impact of a product as well as economic sense of recycling and energy and resource efficiency is growing. Find some case studies about the way that water is used globally. What ideas are out there for using water more efficiently both here in the West and in less developed countries? Are there ideas that you can contribute or an invention you could patent? Why not ask to visit the local sewage treatment plant or the local water treatment plant? Why not investigate how good we are as a school at reducing, re-using and recycling? What can you do about it as a student body? Read the following books The Omnivore’s Dilemma: A Natural History of Four Meals, Michael Pollan Small is Beautiful: Economics as if People Mattered, Ernst F Schumacher Guns, Germs and Steel: The Fates of Human Societies, Jared Diamond Green to Gold: How Smart Companies Use Environmental Strategy to Innovate, Create Value and Build Competitive Advantage, Daniel Etsy Watch the following documentaries: The 11th Hour, 2007 Oceans, 2009 Earth, 2007 Food Inc, 2008 Rexam’s Full Circle Film - the lifecycle of an aluminium can The Great Recovery, RSC RI Christmas Lectures 2010 Watching Cement Dry, STFC List to come podcasts from people campaigning for a more sustainable society.
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GCSE Chemistry required practical activity: Water purification Student sheet Required practical activity
Apparatus and techniques
Analysis and purification of water samples from different sources, including pH, dissolved solids and distillation.
AT 2, AT 3, AT 4
Distillation of salt water to produce potable water You will test salt water for the presence of sodium and chloride ions. You will then distil the water and test the water again. If the ions have been removed the water is now safe to drink. Learning outcomes 1 2 3 Teachers to add these with particular reference to working scientifically
Risk assessment •
Safety goggles should be worn throughout
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Method You are provided with the following: •
10 cm3 salt water
•
Bunsen burner
•
tripod
•
gauze
•
heatproof mat
•
250 cm3 beaker
•
clamp stand
•
250 cm3 conical flask
•
delivery tube with bung
•
test tubes ×2
•
ice
•
test tube rack
•
nichrome wire
•
dilute nitric acid
•
silver nitrate solution
Read these instructions carefully before you start work. 1.
Pour around 1 cm depth of the salt water into a test tube in the rack. Dip the nichrome wire into this solution, and then hold the tip of the wire in a blue Bunsen burner flame. Record your observation in the table such as the one below. A yellow flame test confirms the presence of sodium ions.
Flam e test
Nitric acid and silver nitrate
Salt water Distilled water
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2
2.
Add a few drops of dilute nitric acid to this solution. Then add 1 cm depth of silver nitrate solution. Again, record your observations in the table. A white precipitate with nitric acid and sliver nitrate solution confirms the presence of chloride ions.
3.
Place the remaining salt water in the conical flask. Set up the apparatus for distillation as shown in the diagram.
Make sure the conical flask is held on the tripod and gauze using the clamp stand. Put a mixture of ice and water in the beaker surrounding the test tube. 4.
Boil the water using the Bunsen burner. Then reduce the heat so that the water boils gently. Distilled water will collect in the cooled test tube. Collect about 1 cm depth of water in this way, then stop heating.
5.
Repeat the tests in steps 1 and 2 again using the distilled water. Make sure that the nichrome wire and test tube have been cleaned. Again, record your results in the table.
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