C7 lesson part four

C7 Chemistry ‘triple science’ Route map Over the next 24 lessons you will study : Friday 21 October 2011 C7.1 The alkanes C7.2 The alcohols C7.3 Carboxylic acids C7.4 Esters End of module test C7.5 Fats and oils C7.7 Energy changes C7.15 Chromatography C7.16 Interpretating chromatograms C7.17 Gas chromatography C7.18 Titrations C7.8 How much energy C7.9 How fast...rates of reaction C7.10 Reversible changes C7.11 Equilibrium C7.19 Precision and accuracy C7.20 Overview of the chemical industry C7.21 Green chemistry C7.22 Improving yield in industrial chemistry C7.12 Theories on acidity C7.13 Stages in analysis C7.23 Making industrial chemistry greener C7.24 Reducing waste in industrial chemistry C7.6 Fats and human health C7.14 Sampling C7.25 Using by-products and reducing waste C7.26 Making ethanoic acid

C7.22 Improving yield in industrial chemistry Decide whether the following statements are true or false: Lesson objectives: Understand that the percentage yield of a process is a measure of the efficiency of the process in converting raw material to final products Understand the difference between theoretical yield, percentage yield and actual yield. We will focus on. Friday 21 October 2011 First activity: Think of two industrial process, one a very low yield process and two a very high yield process ? Literacy: Yield, actual yield, theoretical yield, percentage yield, efficiency, raw materials, substrates, products, industry chemistry, calculations and atom economy. Numeracy: In 1998 Barry Trost coined the phrase ‘atom economy’ as a measure of the efficiency in which a reaction uses its reactants or substrates. PLTS Independent enquirers Creative thinkers Reflective learners We will focus on Team workers Effective participators Self managers

Extension questions: 1: Explain the difference between actual and theoretical yield ? 2: Why are product yields rarely 100% ? 3: Ethene, the alkene which is used as a raw material for making polythene is made form ethane. A chemist started with 12 tonnes of ethane and produced 6.5 tones of ethene. What is the theoretical yield, b) the actual yield and c) the percentage yield for this industrial process ? 4: The ethene was than made into 4.5 tones of polythene. Explain the percentage yield of the polythene compared to war materials ? Know this: a: Know that the percentage yield of a process is a measure of the efficiency of the process in converting raw material to final products. b: Know the difference between percentage, actual and theoretical yield. Friday 21 October 2011 Introduction: In chemistry, yield, is the amount of product obtained in a chemical reaction. The theoretical yield can be given as the weight in grams or in moles of the product. The percentage yield, which serve to measure the effectiveness of an industrial process, is calculated by dividing the amount of the obtained product in moles by the theoretical yield in moles. Making sure you delivers the highest yield possible make the process more cost effective and reduces the amount of raw material that you have to purchase C7.22 Improving yield in industrial chemistry

Key concepts C7.22 a Look at the photograph and information and answer all the questions: Look the diagram opposite illustrating the manufacturing process for making ammonia a raw material required to make fertilisers. a) What are the raw materials ? b) Why are the un-reacted raw material recycled ? c) Is the yield of ammonia NH 3 considered excellent good or poor ? The ideal or theoretical yield of a chemical reaction would be 100%, a value that is impossible to achieve in normal industrial processes. Yields around 90% are called excellent , yields above about 80% very good , yields above about 70% are called good , yields below about 50% are called fair , yields below about 40% are called poor . Yields may appear to be above 100% when products are impure. Purification steps always lower the yield and the reported yields usually refer to the yield of the final purified product 56% The Haber process for making ammonia (NH 3 )

Key concepts C7.22 b Look at the photograph and information and answer all the questions: During a reflux reactions yield tend to be low at around 50 to 60%. Reactions are doing using reflux where both reactants meet as vapours with the product being condense back into a liquid and collected. Un-used reactants are recycled over and over again using this apparatus which helps to further improve the yield of organic reactions. product condenser substrates heat Looking at percentage yield Explain the role of reflux in trying to improve the yield of the ester product ? Substrate a: 45.00g Substrate b: 55.00g Product c: 67.00g Substrates Reactants If 45.00 grams of substrate A was reacted with 55.00 grams of substrate B to make 67.00 grams of product C, find or calculate: a) The actual yield ? b) The theoretical yield ? c) The percentage yield ?

C7.22 Plenary Lesson summary: weight measure product dividing Friday 21 October 2011 As a general rule, most reactions do not result in 100% yield, and so, this might be the limits of the reaction. In some cases, one of the reagents that is used in the reaction is limiting and can cause a reduced in yield. How Science Works: Research into improving how new products are made and improving yield efficiency and atom economy. Preparing for the next lesson: In chemistry, yield and reaction yield, is the amount of _______ obtained in a chemical reaction The absolute yield can be given as the _______ in grams or in moles. The percentage yield, which serve to _______ the effectiveness of a reaction, is calculated by _________ the amount of the obtained product in moles by the theoretical yield in moles: Decide whether the following statements are true or false : False True 3: The actual yield is always higher than the theoretical yield ? False True 2: Impure products can sometimes give actual yield that are above 100% ? False True 1: Actual yield of a products is never 100% ?

C7.23 Making industrial chemistry greener Decide whether the following statements are true or false: Lesson objectives: Understand how to improve industrial processes therefore reducing the use of raw materials, energy and the need to manage waste. Understand how to make all the steps of an industrial processes safer and less wasteful therefore reducing the impact on the environment. Friday 21 October 2011 First activity: Think of one industrial process or company that has become greener over the last 20 years, for example Shell now sell bio-ethanol and Liquid Petroleum Gas (LPG) for fuels for cars as well as diesel and petrol ? Numeracy: The use of crude oil as a raw material for fuels, lubricants, bitumen, and plastics has never been higher. The cost of a litre of petrol is expected to rise by 8% per year every year until we exhaust our World reserves. PLTS Independent enquirers Creative thinkers Reflective learners We will focus on Team workers Effective participators Self managers Literacy: Green chemistry, risk assessment, improving yield, actual yield, energy efficiency, reducing raw materials, atom economy and hazardous waste.

C7.23 Extension questions: 1: Give three uses for polythene in the home ? 2: Why does chemists making industrial process more efficient make good a) economic sense and b) environmental sense ? 3: Why do using catalysts reduce a) the time taken for the end product to be made and b) the amount of energy required ? 4: Why are biological powder that work at low temperatures better for the environment ? 5: Name three material that are easy to recycle ? Know this: a: Know how to improve industrial processes therefore reducing the use of raw materials, energy and the need to manage waste. b: know how to make all the steps of an industrial processes greener. Friday 21 October 2011 Introduction: Polythene is made by joining together molecules of ethene. Ethene is made by cracking longer chain alkens forming ethane and then converting into ethene. The yield for this reaction is about 65%. By mixing lots of ethene molecules together, we can make them join onto each other - like links in a chain. In this way, a chain of ethenes links up to make 'poly-ethene', or polythene. Engineers and scientists have radically changed the process of making polyethylene since World War II. The process used today has significantly reduced the production cost of polyethylene. This reduced cost has opened up the market for polyethylene to be used in a wide variety of products including once use food and product packaging. Making industrial chemistry greener

Key concepts C7.23 a Look at the photograph and information and answer all the questions: Aspirin the mostly widely used drug in the world - approximately 35,000 tonnes are produced and consumed annually (100 billion standard aspirin tablets.) Scientists previously used an inefficient two step process which has now been replaced by an efficient one step process. This improved the atom economy of manufacture and reduce costs and waste. Yield 85% Yield 60% Product If the yield increase from 60% to 85% what would this do to the cost of aspirin manufacture ? Why does yield tend to fall as the number of synthesis steps increases during the manufacture of a chemical like aspirin ? Pathway B Pathway A Improving atom economy in industrial chemistry

Key concepts C7.23 b Look at the photograph and information and answer all the questions: The properties of any polymer are determined by two things. a) The length of their chains b) How the fibres interact with one another Scientists can change properties like strength and elasticity by using different catalysts that they use during polythene manufacture. HDPE LDPE PET Cling film In cling film, the polymer chains mostly branched giving a low density. How does introducing ‘cross link’ change the properties of the polythene ? In PET plastic which is used to make drinks containers, the fibres line up end to end allowing high density plastic. Why is this an ideal property for a drinks container ? Catalyst B Catalyst A Using different catalysts in manufacturing plastics

Key concepts C7.23 c Look at the photograph and information and answer all the questions: An industrial chemist will always consider and try and control the costs of every part of the industrial process from the cost of buying in raw materials to the cost of turning them into a new product. Chemists must also include the cost of disposing of waste chemicals and the cost of energy (heat and electricity) require during the manufacturing process. Yield % Product The price of crude oil begins to soar, what cost associated with the process above will begin to rise ? Persil and Arial washing powder/liquids now come super-concentrated, what cost does this reduce and why ? Raw materials Material cost (£) Transport cost (£) Waste cost (£) Process cost (£) Electrical cost (£) Heating cost (£) Product cost (£) Transport cost (£) Waste cost (£) Synthesis pathway Reducing costs from raw material to final product

C7.23 Plenary Lesson summary: drugs improve raw waste Friday 21 October 2011 Atom economy describes the conversion efficiency of a chemical process in terms of all atoms involved. In an ideal chemical process, the amount of starting materials or reactants equals the amount of all products generated. Atom economy is an important concept of green chemistry . How Science Works: Research into how chemist can reduce waste and recycle reactants and finished products when they are no longer needed by the consumer. Preparing for the next lesson: Industrial chemists work very hard to _______ the processes that take ______ materials producing products like dyes, ____, bulk chemicals and fuels. It also make economic sense to reduce _______ and improve the atom economy of the process. Decide whether the following statements are true or false : False True 3: Improving the final yield will increase profits for the chemical industry ? False True 2: Recycling is generally not good for the environment ? False True 1: The cost of polythene and other plastic is linked to the cost of crude oil ?

C7.24 Reducing waste and recycling chemicals Decide whether the following statements are true or false: Friday 21 October 2011 First activity: Think of one use for recycled PET plastics and how could you green the way you lived in your own home ? Numeracy: In 2010 over 2.2. trillion pounds of PET plastic were produced worldwide. About 25% of the original plastic was recycled into new plastic products. PLTS Independent enquirers Creative thinkers Reflective learners We will focus on Team workers Effective participators Self managers Lesson objectives: Understand how to improve industrial processes therefore reducing the use of raw materials, energy and the need to manage waste. Understand how design products that can be recycled, therefore reducing waste to landfill. Literacy: Green chemistry, risk assessment, improving yield, actual yield, energy efficiency, reducing raw materials, atom economy hazardous waste.

Extension questions: 1: Why has the government change the law to make all council recycle at least 25% of all household waste ? 2: Suggest two benefits and two disadvantages to recycling plastic like polythene and PET plastics ? 3: Give the raw material for the following products a) milk carton b) glass bottle c) PET plastic bottle and d) rubber tyre ? 4: In the 1970s bottle and can makers use to have a deposit system on their cans and bottle. Why does this encourage recycling ? Know this: a: Know how to improve industrial processes therefore reducing the use of raw materials, energy and the need to manage waste. b: Know how design products that can be recycled, therefore reducing waste to landfill. Friday 21 October 2011 Introduction: Industrial chemists make sure that during product manufacture from raw materials, there is as little waste a possible. Key things all chemists consider are: Atom economy: (improving pathways of synthesis and therefore reducing quantities of raw materials required) Life cycle of the product: (improving the life cycle of a products, for example a plastic bag has a life expectancy of only 25 minutes before it is binned) Using by-products: (can by products be useful, for example the whey liquid removed form the curds during cheese manufacture is now used to make animal feed) Reducing waste and improving recycling: (Can your product by recycled, for example rubber tyres are now used to make wellies, astro-turf and door mats.) C7.24 Reducing waste and recycling chemicals

C7.24 a Look at the photograph and information and answer all the questions: Explain why wellington boots using recycled rubber are cheaper to make than wellington boots made form new raw materials ? Can you think of any other uses for the 40,000,000 tyres that we use every year here in the UK alone ? Key concepts Wellies tyres Door mats landfill Astro turf Tyres are made form cured rubber which is collected as liquid latex form the rubber tree. Rubber tyres are tough and durable, and they have to be. An average car tyre will travel around 20,000 miles over its lifetime. But what happens when they reach the end of the road?. Currently, around a quarter of old tyres are reused and around half are recycled in some way. To make up the shortfall, there are some imaginative ways to give an old tyre a new lease of life including; turning the rubber into a) Wellington boots, b) atsro-turf and c) door mats. Life cycle of tyres

Key concepts C7.24 b Look at the photograph and information and answer all the questions: Look at the process above, explain whether this is open loop or closed loop recycling ? Give three ways that we can encourage individuals and households to recycle more of their PT plastics ? Plastics are sorted according to their resin code, a method of categorization of polymer types. Polyethylene terephthalate or PET has a resin code of 1. They are also often separated by colour and then shredded. These shredded fragments then undergo processes to eliminate impurities like paper labels. This material is melted and often extruded into pellets which are then used to manufacture other products. Recycling PET (1) plastics PET flakes reused to make more PET bottles

C7.24 Plenary Lesson summary: polymer sorted glass mix Friday 21 October 2011 PET bottles are also recycled as-is (re-used) for various purposes, including for use in school projects, and for use in solar water disinfection in developing nations, in which empty PET bottles are filled with water and left in the sun to allow disinfection by ultraviolet radiation. PET is useful for this purpose because other materials (glass) that are transparent to light are opaque to UV radiation. How Science Works: Research into using by products and reducing pollution by reducing waste. Preparing for the next lesson: When compared to other materials like _______ and metals, plastics require greater processing to be recycled. Different plastics are difficult to _____, which is due to the large ________ chains. Heating alone is not enough to dissolve such a large molecule, they have to be very closely _______ into different types and colours . Decide whether the following statements are true or false : False True 3: Carpet and fleece fibres are made form recycled PET bottles ? False True 2: Recycling increase the impact on the environment ? False True 1: Recycling material is often better value for money ?

C7.25 Using by products and reducing pollution Decide whether the following statements are true or false: Friday 21 October 2011 First activity: Compare how you buy your milk, doe it come in a multi use milk bottle or a one use milk carton. Which do you think is the more environmentally way to receive your milk ? Numeracy: A glass milk bottle is used on average 125 times before it can then be recycled into other glass products. PET bottle are used once before only 25% of the plastic are recycled into new plastic PET bottles. PLTS Independent enquirers Creative thinkers Reflective learners We will focus on Team workers Effective participators Self managers Lesson objectives: Understand how to improve industrial processes therefore reducing the use of raw materials, energy and the need to manage waste. Understand how by products can be used to increase profits and reduce pollution. Literacy: Green chemistry, risk assessment, improving yield, actual yield, energy efficiency, reducing raw materials, atom economy, by products, reduce, reuse and hazardous waste.

C7.25 Extension questions: 1: Give one commercial use for the following by-products a) clinker produced from iron extraction b) chlorine gas form the production of bleach from salt brine c) plant fibre form the extraction of sugar from sugar cane ? 2: Describe the difference between reusing, recycling and reducing and what household items could you a) reduce b) reuse and c) recycle ? 4: What type of material are we now encouraged to recycle in our everyday lives ? Know this: a: Know how to improve industrial processes therefore reducing the use of raw materials, energy and the need to manage waste. b: Know how by products can be used to increase profits and reduce pollution. Friday 21 October 2011 Introduction: Most chemical process produce vast amounts of by-products that if not used can pollute the environment. Using by-products to produce other new products makes good commercial sense: Creates new products: (these add value to your company’s product range and market share) Generates additional income: (this can increase your company's profit) Reduces waste: (often you have to pay to manage waste reducing your waste will save you money and time) Improves the efficiency of the process: (less material, storage and distribution costs) Using by-products and reducing pollution

Key concepts C7.25 a Look at the photograph and information and answer all the questions: Why has the government introduced new law forcing 5% of all fuels that are sold for cars and lorries to be bio-fuels ? There three main by-products produce whilst making biofuels are list above. Explain why these are now also important products in their own right ? The chemical by-products generated from biodiesel production have a number of commercial uses: Glycerine : A colourless, nontoxic liquid use in foods, for example, as a sweetener or softening agent, in personal care products, for example, in soap, shampoo and lotion. Plant asphalt: Carbon rich used as a fuel for boilers, casting plaster and a stain remover. Erucic acid: A fatty acid that can be extracted from rapeseed and used in the production of lubricants and polyesters, for example, in skin and health care products By-products from making bio-fuels raw materials Industrial process Products and by-products

Look at the photograph and information and answer all the questions: Here in the Europe, our consumer lifestyles means that we use lots of natural resources and produce lots of waste or rubbish. A large percentage of UK households still do not recycle, reduce or reuse in their everyday lives. Most people over consume, fail to reuse or recycle everyday objects. By recycling, reducing and reusing we can lessen our environmental impact. Plastic especially in packaging is often used only once and then buried in land fill sites...suggest one way you can reduce the amount of plastic you use ? Suggest one product that you can a) reuse and b) recycle ? Used plastic that is buried in landfill sites takes many years to breakdown. Scientists have now developed biodegradable plastics. Do you think that all plastics now sold should be biodegradable ? Key concepts C7.25 b

C7.25 Plenary Lesson summary: waste markets process polltute Friday 21 October 2011 New legalisation is being introduced every year to ensure that companies pollute less and produce less landfill waste. The current policy is that the ‘polluter pay’s meaning that companies now have to pay for the right to dump waste either into landfill or via the sewerage system. How Science Works: Research into how the manufacturing of ethanoic acid (acetic acid or vinegar) has changed over the last 30 years making the process more efficient and lest costly. Preparing for the next lesson: In any industrial __________, it is impossible to eliminate ________ completely, however by finding new ___________ for some for the by products companies can _______ less and make more profit. Decide whether the following statements are true or false : False True 3: Processed cheese found in hamburgers is a by-product of butter manufacture ? False True 2: Plaster board is made from waste gypsum created by cement manufacture ? False True 1: By using by-products for different products companies can reduce waste ?

C7.26 Making ethanoic acid…a case study Decide whether the following statements are true or false: Lesson objectives: Understand how the uses for ethanoic acid and how it is manufactured Understand how the manufacturing process for making ethanoic acid has changes over the last 30 years improving atom economy Friday 21 October 2011 First activity: Ethanoic acid or vinegar is used in a wide range of products. Give three uses of ethanoic acid or vinegar ? Literacy: Ethanoic acid, acetic acid, vinegar, carboxylic acid, industrial processes, raw material, substrates, products, atom economy and greener chemistry. Numeracy: The global demand of acetic acid is around 6.5 million tonnes per year, of which approximately 1.5 million tonnes is met by recycling; the remainder is manufactured from petrochemicals, feed stocks or from biological sources . PLTS Independent enquirers Creative thinkers Reflective learners We will focus on Team workers Effective participators Self managers

Extension questions: 1: Why could you not put ethanoic acid made by oxidising crude oil hydrocarbons on your fish and chips ? 2: Explain why using crude oil hydrocarbon was not an environmentally friendly way of making ethanoic acid ? 3: Name four foods preserved in fermented ethanoic acid (vinegar) ? 4: Other than improving the yield, what other costs may have been lowered by making ethanoic acid form reacting methanol with carbon monoxide using a catalyst ? Know this: a: Know how the uses for ethanoic acid and how it is manufactured b: Know how the manufacturing process for making ethanoic acid has changes over the last 30 years. Friday 21 October 2011 Introduction: Ethanoic acid (CH 3 COOH) is organic carboxylic acid . It is an important chemical reagent and industrial chemical which is also used in foods as a preservative. It is very widely used as a solvent and in the manufacture of rubber and plastics. It is also used in the production of PET plastics. In the food industry, ethanoic acid is produced by natural fermentation and is used under the food additive code E260 as an acidity regulator and as a condiment (think fish and chips !). Prior to 1970, it was made by oxidising hydrocarbons sourced from crude oil. This process was expensive and yielded about 30% ethanoic acid. It is now made by reacting methanol and carbon monoxide reducing waste and yielding almost 100% C7.26 Making ethanoic acid…a case study

Key concepts C7.26 a Look at the photograph and information and answer all the questions: Explain why a) the substrates are heated and b) the un-reacted substrates are recycled during this process ? Look at the entire process and explain why you would expect to have any waste products or by products ? In the 1970s the Monsanto Chemical Company found a method for making ethanoic acid (CH 3 COOH) directly by reacting methanol (CH 3 OH) and carbon monoxide (CO) instead of oxidising valuable hydrocarbons extracted from crude oil. CH 3 OH (l) = CO (g) CH 3 COOH (l). + C=O raw materials end product recycling substrates heater pump reactor condenser Manufacturing ethanoic acid from methanol and carbon monoxide

Key concepts C7.26 b Look at the photograph and information and answer all the questions: The process Why do industrial chemists analyse each stage of an industrial process ? Explain the difference between a by-product and a waste material ? Raw materials Industrial process By-products Waste materials Can the amount of raw material be reduced to improve atom economy ? Can the process be made more energy efficient to reduce operating costs ? Is the yield as high as possible ? Questioning the process Can any of the by products be sold or reused ? Product yield Can the amount of waste material be reduce avoid landfill charges ? Atom economy (atom efficiency) describes the conversion efficiency of a chemical process in terms of all atoms involved. In an ideal chemical process the amount of starting materials or reactants equals the amount of all products generated and no atom is wasted. Recent developments like high raw material (such as petrochemicals) costs and increased sensitivity to environmental concerns have made atom economical approaches more popular. Atom economy is an important concept of green chemistry philosophy reducing the use of raw material and the production of waste Improving industrial chemical processes

C7.26 Plenary Lesson summary: profit pathways by-products raw Friday 21 October 2011 When you are producing millions of tonnes of bulk chemicals even a 0.1% increase in yield can save you millions in pounds on raw materials and energy and whilst also increasing profit by similar amounts. Some companies now reward directly employees who improve yield by giving them a share of the saving made or the increases in profit. How Science Works: Prepare for an end of module test. Preparing for the next lesson: Using direct synthesis __________, catalysts and finding new markets for __________ as well as reducing ______ materials reduces the operating cost of a process and increase the profit of a chemical company. Decide whether the following statements are true or false : False True 3: High yield process are bad for the environment ? False True 2: Direct synthesis route using catalysts often increase product yield ? False True 1: Low yields mean more expensive products and less profits ?

C7 lesson part four

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C7 lesson part four