Optional: Consumer Chemistry

Unit Overview

How can chemistry help us understand how a product works? Why is a product effective? What chemicals is a product made of? Did the idea for the product originate in a property of a chemical and the search for an application for that property? Did it originate in a perceived need and the search for a chemical or substance to fulfil that need?

One instructional method which may work in this unit is to assign each student or group of students one or more or the questions posed in the Suggested activities section of the unit. Each student or group would be responsible for preparing a presentation to the class, reporting the results of their research. Encourage students to use a wide range of reporting techniques. Posters, poems, video reports, and models are some of the options.

Factors of scientific literacy which should be emphasized

• A1 ..........public/private
• A3 ..........holistic
• A7 ..........unique
• A9 ..........human/culture related
• B12 ..........conservation
• B16 ..........system
• C1 ..........classifying
• C2 ..........communicating
• C3 ..........observing and describing
• C6 ..........questioning
• C8 ..........hypothesizing
• C9 ..........inferring
• C10 ..........predicting
• C12 ..........interpreting data
• C15 ..........analyzing
• C16 ..........designing experiments
• C19 ..........consensus making
• D1 ..........science and technology
• D2 ..........scientists and technologists are human
• D4 ..........science, technology, and the environment
• D6 ..........resources for science and technology
• D8 ..........variable positions
• D9 ..........social influence on science and technology
• D11 ..........science, technology, and other realms
• E2 ..........using natural environments
• E9 ..........measuring volume
• E11 ..........measuring mass
• E13 ..........using quantitative relationships
• F2 ..........questioning
• F3 ..........search for data and their meaning
• F4 ..........valuing natural environments
• F6 ..........consideration of consequence
• G1 ..........interest
• G3 ..........continuous learner
• G5 ..........avocation

Foundational Objectives for Chemistry and the Common Essential Learnings

Investigate the chemical principles involved in the composition, production or functioning of consumer products.

• Identify chemicals in the components of consumer products.
• Classify the components as either structural or functional.
• Discuss how the chemicals selected are suited for their function.
• Suggest alternatives or substitutes for the chemical components in a product.

Describe and discuss the impact of the chemical industry on society.

• Explain the role of chemistry in the manufacture of consumer products.
• Investigate how chemistry has led to advances or innovations in various consumer products.
• Show how the application of chemistry in consumer products has led to changes in health and lifestyle.
• Investigate the impact of chemicals from consumer products on the environment.
• Understand how chemistry can be used to help make informed consumer decisions.

Develop a contemporary view of chemical technology and its influence on our lives. (TL)

• Examine experiences with and contact with chemical technology in the home and community.
• Understand the political, social and consumer demands which create and sustain technological developments.
• Understand how technological developments can create and sustain consumer demand.

Develop a positive disposition to life-long learning. (IL)

• Cooperate with and help each other in order to enhance understanding through shared information.
• Plan investigations into topics in chemistry.
• Develop a willingness to take risks as independent learners.
• Recognize the inevitability of profound change due to advancement in technology and changes in society's values and norms.
• Understand how change can be influenced by those who keep themselves informed.

Suggested activities and ideas for research projects

• 18-carat gold contains 75% gold. The rest is silver and copper in varying proportions. 18-carat gold is harder than pure gold. A 50% solution of antifreeze in water freezes at a lower temperature than either pure water or pure antifreeze. Are these two phenomena related?

• How does adding gallium or arsenic to pure silicon chips allow the silicon to conduct electricity?

• What chemicals are found in cream blushes and in powder blushes?

• It takes approximately 5% as much energy to manufacture an aluminum can from a recycled can as from the bauxite ore. Outline the chemical processes involved in producing aluminum from bauxite. Which of the processes require the greatest energy inputs?

• Investigate the production and recycling of automobile batteries. What are the main chemicals and processes involved?

• What is acid indigestion? What acids are involved? How do antacid tablets combat acid indigestion?

• Cars are one of the worst sources of air pollution in urban North America? What chemical compounds are emitted from cars? By what chemical processes are these compounds formed?

• Home safety books say that one should never mix bleaches with other cleaners. Why?

• How are bleaches which are advertised as safe for all fabrics or as being `bleach for the unbleachables' different from other bleaches? How effective are they? By what process does each type of bleach work?

• What are some chemicals which can be used as sunscreens? How does each one prevent ultraviolet radiation from reaching the skin? How are do sunblocks work? What chemicals are used as sunblocks?

• What chemicals are involved in acne remedies? Do they act on the cause of the acne, remove the symptoms or mask the symptoms? How do the chemicals affect the skin, the gland ducts and the bacteria?

• What dyes are used in eye shadow? In what medium is the dye suspended? What are the sources of these dyes? What are some other uses of the dyes?

• Compare and contrast the chemicals used in lip gloss, regular lipstick and frosted lipstick.

• What are the active chemicals in hair gels and mousse? Are these the same chemicals which are used in hair sprays? Are these chemicals or similar chemicals used in any other applications?

• How are detergents chemically different from soaps? How does this difference affect their abilities to clean? What are the advantages of each class of product?

• How are a facial soap, a body soap, an anti-bacterial soap and a European bathing gel chemically similar? How are they different?

• Find out how to make soap using lard and lye. Make some soap and devise tests to see how the soap compares to commercially produced soaps. Use caution when using the soap on the skin. The soap may be caustic if not all the lye has been neutralized. Try canola oil or olive oil instead of lard.

• All members of the group of chemicals called alcohols have an -OH group on a carbon chain. How are all steroids similar? What are some steroids which the human body produces? How do steroids such as stanozolol aid muscle growth? How do synthetic steroids compare to natural steroids?

• Most fertilizers contain nitrogen, potassium and phosphorus. What are these nutrients used for in plants? How do they get from the ground into the plant? What other nutrients are needed for plants? Why don't we hear as much about these other nutrients in fertilizers? For each mineral nutrient which a plant needs, identify one natural compound or source in the soil for this nutrient.

• Some fertilizers for houseplants are advertised as 'slow-release' fertilizers. What does that term mean with respect to fertilizers? How are slow release fertilizers produced?

• What chemical compounds are found in pink fibreglass insulation? How is it produced? Can recycled glass be used to make fibreglass?

• Food additives can be used for more than preserving food. How many different purposes can you identify?

• If an apple is dipped in ascorbic acid solution or lemon juice as soon as it is cut, the apple's surface won't turn brown as quickly? What is the chemical reaction which turns the apple brown and how does the citric acid solution prevent this?

• Do chemicals which are used as food additives undergo chemical reactions with the food or are they just mixed in with the food?

• Go to a grocery store and make a list of the ingredients in each brand of ice cream that is sold there. For each brand, make a poster listing each ingredient, its chemical formula or the class of compounds to which it belongs and the reason the substance is used.

• When liquid egg white is dropped on a hot frying pan it turns to a white solid immediately. What chemical reaction is involved in this change? Drop some vinegar or some lemon juice into some liquid egg white. What changes can you observe? Sketch diagrams or create a model to show the chemical reaction which occurs.

• Poisons which affect humans can be classified as either neurotoxins or hemotoxins. Is there a way to classify herbicides based on what part of the plant they affect? How is the way a herbicide affects a plant related to the type of chemical?

• Are herbicides manufactured in Saskatchewan? What raw materials are used in their production?

• Recent reports indicate that drinking some liquids which have been stored in lead crystal containers may be hazardous. What is lead crystal? What is the hazard? What type of liquids cause the problem? Many paints used to use lead-based pigments. Why were lead-based pigments used? What chemicals are found in most paints now? How are these pigments produced?

• Potters often make their own glazes. What chemicals are used in the preparation of these glazes? What hazards are produced when the glazes are fired?

• How is phototropic glass produced? Is the reaction which occurs when the glass turns darker with exposure to light completely reversible? How long does it take the glass to darken? Is there a limit to how dark the glass can become?

• How many different types of plastics can you identify in products in your school and home? Make a poster listing the type of plastic (e.g. high density polyethylene), several uses for that type, the formula of the monomer or dimer and indicate the sites at which the monomer or dimer polymerizes.

  For each product you can identify which is partially or entirely made of plastic, find out what materials were used for that part or product before plastics were developed. If the product has been developed after plastics have become prevalent, and so has never been made of another material, indicate that.

• How does Freon^TM produce its cooling effect in refrigerators? What harm does it cause when it escapes into the atmosphere? Write the chemical equations which illustrate the harm it does.

• How many uses are there for hydrogen peroxide? Some first aid books recommend that hydrogen peroxide be purchased in as low concentration and stored at as low a temperature as possible. Why would they make these recommendations?

• How does rust form on metals? How are the paints that are advertised as being rust inhibitors different from other paints?

• If you have a car with an aluminum block, why is it important to buy antifreeze that is 'aluminum compatible'? What would be the chemical effects of using incompatible antifreeze?

• Gasoline, fuel oil, diesel fuel and kerosene (jet fuel) are all extracted or refined from crude oil. What are the differences in the products? Explain in terms of the chemical constituents of each mixture.

• Emergency flares can be purchased to burn at the side of a road behind a disabled vehicle or to shoot from a launcher for fliers or boaters who have been marooned. What chemicals are in the flares to make them burn so brightly? Have you ever had a birthday cake with sparklers on it? What chemicals are used to make those type of sparklers?

• Synthetic fabrics are very common. Make a poster listing the common or trade names of synthetic fabrics and what chemical or compound each is composed of.

• Research into the chemical components of natural fibres. How does a wool fibre differ chemically from a cotton fibre? Why are wool fabrics rough and scratchy while fabrics of silk are smooth and soft? What other natural fabrics are there?

• The labels of many household products have the corrosive, toxic or flammable symbols on them. Make a list of these products, categorizing them by type of risk. Seven groups will be enough to separate them into all possible combinations (toxic and corrosive, etc.). Identify as many noncorrosive, nontoxic or nonflammable substitutes as possible. Consider the advantages and disadvantages of using the substitute products.

• Most people know that the most of the gold used for making jewellery comes from gold mines. Make an inventory of everything in your classroom. Identify the chemical components of each item in your inventory and list the source of that component. How many of these resources are produced in Canada? For example, a Bic ballpoint pen might be analyzed as follows:
  • plastic barrel - polycarbonate plastic from crude oil
  • plastic plug in the end of the barrel - polyethylene from crude oil
  • plastic ink tube - polyethylene from crude oil
  • metal support for ball - alloy of copper and zinc, both from mines
  • ball - nylon, synthesized from organic acids and alcohols derived from crude oil

• How is stainless steel made rust resistant? Why can't cars be made from stainless steel? How are manufacturers attempting to make their cars more rust resistant?

• How is the glass used in stained glass art coloured? What chemicals are used as pigments? Is the pigment on the surface of the glass or does it permeate the glass? Do the pigments react chemically with the glass or do they remain with the glass as a mixture or a surface coating?

• The search for diamonds has come to Saskatchewan. What is the chemical formula of diamond? How are they formed in nature? How are synthetic diamonds formed?

• What are the elements and compounds in the material used to fill cavities in teeth? When are metal fillings used? When are plastic fillings used? Ultraviolet light is used to cure the plastic fillings. What chemical changes does the uv light induce in the plastic?

• Sodium sulphate is a mineral which is produced in several locations in southern Saskatchewan. How is the chemical concentrated and purified? What is the market for sodium sulphate?

• Ceramic tiles are used on the heat shield of the space shuttles. They are also used as flooring and wallcoverings. What effect does the firing process during their manufacture have on the chemical structure of the clay they are made from? Does the glaze react chemically with the clay? What chemical changes occur in the glaze during firing?

• How is a perfume different from a cologne of the same fragrance? Is the type of solvent different? Is the concentration of the fragrance molecule in the solvent different? Is a different fragrance molecule used?

• Some photographic processors are advertising that they use a process which removes heavy metal ions and toxic solvents from the water before it is disposed. What heavy metals are used in photography? What solvents are used in developing film? How are these removed from the waste water before it enters the sewage system?

• Many products we use are welded by electric arc welding. Welding rods normally have a metal core and an outer coating. What metal is the core composed of? What is the function of the core? Does it react chemically with the metals to be welded? What chemicals are used to coat welding rods? What is their function? What chemical reactions are they involved in?

• One form of arc welding is called gas shielded arc welding. MIG and TIG welding are examples of this process. What gases are used in the gas shielding process? What do these gases shield the weld from? How do they shield it?

• How many types of processes are there for home water softening? What are the ions which must be removed from water to make it soft? What chemical reactions are involved in removing these ions?

• A number of years ago there were several instances of children receiving severe burns when the fleece material of their pyjamas caught fire. Children's pyjamas are now treated with flame retardants. What other fabrics are treated with flame retardants? What chemicals are used to produce the flame retardant effect? How do these chemicals act to inhibit burning?

• Suppose that legislators became concerned about the use of fossil fuels for running private vehicles. What types of laws/recommendations could they make in order to half the amount of fuel use in private vehicles.

• Suppose legislators decided that in order to conserve crude oil and natural gas, the amount of these resources consumed for the production of plastics would be cut by 10% a year for five years. You were appointed to a board which would make recommendations about places where plastic use could be reduced. What are some recommendations you could make?

• Sulphur is a by-product of the natural gas extraction industry. What uses are there for the sulphur removed from sour gas? How is the sulphur extracted from natural gas?

• Coal contains sulphur. What is the impact on the environment if when the coal burns, sulphur oxides escape into the air? Can the sulphur be removed from the coal before it is burned? Can the sulphur oxides be removed from the smoke? What is coal used for? Are there any fuels which could replace coal? What risks or costs are associated with these substitutes? Could coal be used to replace other fuels we currently use?

• Lots of information and ideas for investigations about food additives can be found in the article "Food Additives" in CHEM13 NEWS, #207, November 1991, pages 8-9.