identify various constraints that result in tradeoffs during the development and improvement of technologies (e.g., identify constraints such as cost and care for the environment when using freon for refrigerators and air conditioners or when deciding on the degree to which petroleum will be refined)
distinguish between scientific questions and technological problems (e.g., distinguish between questions such as How are PCBs converted into dioxins? and technological problems such as how we can dispose of contaminated samples)
explain how a major scientific milestone revolutionized thinking in the scientific communities (e.g., explain how Kekulé's invention of the concept of the ring structure of benzene revolutionized thinking in chemistry)
explain how scientific knowledge evolves as new evidence comes to light (e.g., explain how the concept of the ring structure of benzene was the basis for a lot of new research in organic chemistry)
describe and evaluate the design of technological solutions and the way they function, using scientific principles (e.g., evaluate the way a herbicide that is not toxic to humans and does not accumulate in the environment functions)
analyse natural and technological systems to interpret and explain their structure and dynamics (e.g., analyse the numerous steps involved in the refining of petroleum to obtain gasoline and a variety of additives for car engines)
debate the merits of funding specific scientific or technological endeavours and not others (e.g., debate the merits of funding the development of drugs to combat AIDS rather than research on alcoholism)
provide examples of how science and technology are an integral part of their lives and their community (e.g., provide examples like the banning of lead gasoline because of its impact on the environment, which resulted in consumers using unleaded gasoline)
analyse from a variety of perspectives the risks and benefits to society and the environment of applying scientific knowledge or introducing a particular technology (e.g., analyse the risks and benefits of using insecticides such as DDT)
evaluate the design of a technology and the way it functions, on the basis of a variety of criteria that they have identified themselves (e.g., evaluate the environmental impact of various refrigerants)
define and delimit problems to facilitate investigation (e.g., define and delimit problems such as "Which alkane is the most efficient source of energy?" or limit a study of the yield of an organic reaction to only the effect of temperature)
design an experiment identifying and controlling major variables (e.g., design an experiment to test the resistance of a variety of plastics to heat or forces)
select and integrate information from various print and electronic sources or from several parts of the same source (e.g., research the uses of the most commonly synthesized organic compounds)
select and use apparatus and materials safely (e.g., select and use apparatus safely in the distillation of alcohol or the synthesis of nylon)
identify limitations of a given classification system and identify alternative ways of classifying to accommodate anomalies (e.g., identify examples such as the persistence of non-IUPAC names such as "acetone," and "acetic acid")
identify and apply criteria, including the presence of bias, for evaluating evidence and sources of information (e.g., evaluate, with regard to their environmental claims, advertisements for ethanol blended gasolines)
provide a statement that addresses the problem or answers the question investigated in light of the link between data and the conclusion (e.g., suggest whether or not the use of freon and leaded gasoline should be encouraged in developing countries)
communicate questions, ideas, and intentions, and receive, interpret, understand, support, and respond to the ideas of others (e.g., discuss, as a team, the procedures used in the synthesis of ASA in the laboratory)
synthesize information from multiple sources or from complex and lengthy texts and make inferences based on this information (e.g., synthesize information from multiple sources on the use of DDT)
develop, present, and defend a position or course of action, based on findings (e.g., debate the question "Is petroleum more useful to society as a source of energy or as a source of synthetic materials?")
explain the large number and diversity of organic compounds with reference to the unique nature of the carbon atom
write the formula and provide the IUPAC name for a variety of organic compounds
define isomers and illustrate the structural formulas for a variety of organic isomers
classify various organic compounds by determining to which families they belong, based on their names or structures
write and balance chemical equations to predict the reactions of selected organic compounds
describe processes of polymerization and identify some important natural and synthetic polymers
Organic chemistry is an important component of the study of biochemistry, bioengineering, medicine, and synthetic chemistry. Students should be aware of the process of converting carbon-bearing resources into basic organic molecules that are then turned into a wide variety of plastics, fuels, and pharmaceuticals. This illustrative example emphasizes the social and environmental contexts of science and technology.
Students identify different synthetic organic compounds in their classroom, in their homes, and in the environment. As well, students identify how many of the organic compounds are harmful or helpful to living things.
The above exploration may lead to the following question:
What are the risks and benefits to society and the environment of developing new synthetic products?
Students study the unique properties of carbon with a focus on the bonds that form between carbon atoms. Bond characteristics that may be considered include strength; single, double or triple bonds; and structure long, straight, or branched chains or ring.
Students build, draw, and name models of a variety of organic compounds.
Students carry out a risk-benefit analysis of activities that produce dioxins as by-products. These activities could be the burning of household waste in the backyard, the incineration of toxic wastes, or various industrial processes.
Students can choose a synthetic material and carry out a practical investigation of some properties like physical strength, effect of solvents, and combustibility. In conjunction with the investigation, students obtain and present information related to the properties, cost, uses, possible hazards, means of production, and social and economic implications of the chosen material.
Students can synthesize an organic compound such as aspirin, nylon, or an ester.
This illustrative example suggests ways students can be led to attain the following learning outcomes:
STSE: 117-5, 118-2, 118-4
Skills: 212-2, 213-8
Knowledge: 319-4, 319-5, 319-7, 319-8
Attitudes: 439, 443, 447
explain the roles of evidence, theories, and paradigms in the development of scientific knowledge (e.g., explain how the realization that some acidic substances contained no hydrogen in their formula led to a revision of the Arrhenius theoretical definition of acids)
explain the importance of communicating the results of a scientific or technological endeavour, using appropriate language and conventions (e.g., explain the importance of using appropriate terminology when discussing issues like acid rain or when cleaning up a toxic spill)
explain how scientific knowledge evolves as new evidence comes to light and as laws and theories are tested and subsequently restricted, revised, or replaced (e.g., trace the development of the acid-base theories up to and including the Brønsted-Lowry definition)
analyse and describe examples where scientific understanding was enhanced or revised as a result of the invention of a technology (e.g., describe examples such as how the use of various indicators to determine pH enhanced the comprehension of acids and bases)
analyse society's influence on scientific and technological endeavours (e.g., analyse society's demand for products of a certain pH, such as shampoos and antacids)
identify and describe science- and technology-based careers related to the science they are studying (e.g., describe careers in the areas of pharmacology and chemical engineering)
construct arguments to support a decision or judgement, using examples and evidence and recognizing various perspectives (e.g., suggest acceptable procedures that could be used to study an environmental issue such as a toxic spill or acid rain)
state a prediction and a hypothesis based on available evidence and background information (e.g., predict the relative acidity of different citrus fruits)
evaluate and select appropriate instruments for collecting evidence and appropriate processes for problem solving, inquiring, and decision making (e.g., select an appropriate acid-base indicator to perform a titration)
use instruments effectively and accurately for collecting data (e.g., manipulate burettes and other instruments used for titrations)
select and use apparatus and materials safely (e.g., safely handle and dispose of acids and bases)
demonstrate a knowledge of WHMIS standards by selecting and applying proper techniques for handling and disposing of lab materials (e.g., use appropriate techniques for handling and disposing of acids and bases)
describe and apply classification systems and nomenclature used in the sciences (e.g., name acids and bases using accepted nomenclature)
identify a line of best fit on a scatter plot and interpolate or extrapolate based on the line of best fit (e.g., predict the concentration of an acid from a graph that links concentration of an acid to that of a neutralizing antacid)
interpret patterns and trends in data, and infer or calculate linear and nonlinear relationships among variables (e.g., use titration curves to determine an end point)
identify new questions or problems that arise from what was learned (e.g., identify environmental problems that may be created when attempting to neutralize an acid spill)
select and use appropriate numeric, symbolic, graphical, and linguistic modes of representation to communicate ideas, plans, and results (e.g., present a detailed experimental report according to specific standards)
work cooperatively with team members to develop and carry out a plan, and troubleshoot problems as they arise (e.g., work cooperatively while performing titrations)
describe various acid-base definitions up to the Brønsted-Lowry definition
predict products of acid-base reactions
compare strong and weak acids and bases using the concept of equilibrium
calculate the pH of an acid or a base given its concentration, and vice versa
describe the interactions between H+ ions and OH- ions using Le Châtelier's principle
determine the concentration of an acid or base solution using stoichiometry
explain how acid-base indicators function
Students regularly use solutions that include acids and bases. It is important that students be able to demonstrate their understanding of acids and bases by appropriately selecting the proper acid and base to use for a given task. As well, students should be aware of the potential effects these chemicals could have on the environment. Students' knowledge and interests are enhanced when they understand the relationship between acid-base theories and certain acid-base reactions that take place around them. This illustrative example emphasizes the nature of science and technology.
Students identify common products where acids and bases are involved, such as shampoos, foods, and household cleaners. They should be encouraged to speculate as to how acids and bases react in the situations they identify.
The above exploration may lead to the following question:
Why are specific acids and bases used in particular instances?
By studying the historical development of acid-base theory, students will be able to show how theories evolve in light of new experimental evidence.
Students will formulate an operational definition of acids and bases based on laboratory observations.
In a laboratory setting, students will determine the concentration of an acid or a base, the citric acid concentration of a citrus fruit, or the acetylsalicylic acid (ASA) content of a headache tablet.
Students should be presented with the opportunity to address an environmental issue pertaining to acids and bases. Working as a team, they would be expected to present factual arguments representing various perspectives.
This illustrative example suggests ways students can be led to attain the following learning outcomes:
STSE: 114-2, 115-7,
Skills: 213-8, 214-4, 215-2
Knowledge: 320-1, 320-7
Attitudes: 447, 449
explain the roles of evidence, theories, and paradigms in the development of scientific knowledge (e.g., explain superconductivity using bonding theory)
explain how scientific knowledge evolves as new evidence comes to light and as laws and theories are tested and subsequently restricted, revised, or replaced (e.g., explain how our understanding of chemical bonds has improved as a result of using more advanced technologies that help us know more about atoms)
analyse and describe examples where technologies were developed based on scientific understanding (e.g., use examples such as sports equipment, some of which is made from alloys and new materials like composites, and filling teeth with composite resins instead of alloys)
analyse examples of Canadian contributions to science and technology (e.g., analyse examples such as Raymond Lemieux's work on molecular recognition in oligosaccharides)
analyse from a variety of perspectives the risks and benefits to society and the environment of applying scientific knowledge or introducing a particular technology (e.g., analyse a particular technology such as changing the bonds formed by using ozone rather than chlorine to disinfect water, thus preventing toxic chlorinated hydrocarbons from forming in treated water supplies)
identify the theoretical basis of an investigation and develop a prediction and a hypothesis that are consistent with the theoretical basis (e.g., use bond theory to predict properties of compounds)
use library and electronic research tools to collect information on a given topic (e.g., collect information on the chemical and physical properties of compounds)
select and integrate information from various print and electronic sources or from several parts of the same source (e.g., investigate the use of chemical and physical properties of compounds in various contexts)
describe and apply classification systems and nomenclatures used in the sciences (e.g., apply IUPAC nomenclature for ionic compounds)
identify limitations of a given classification system and identify alternative ways of classifying to accommodate anomalies (e.g., identify the limitations of using electronegativity values to determine the polar nature of a specific covalent bond)
compile and display evidence and information, by hand or computer, in a variety of formats, including diagrams, flow charts, tables, graphs, and scatter plots (e.g., display visually models that explain intermolecular and intramolecular forces)
select and use appropriate numeric, symbolic, graphical, and linguistic modes of representation to communicate ideas, plans, and results (e.g., represent ionic and molecular compounds by their accepted formulas and names)
illustrate and explain the formation of ionic, covalent, and metallic bonds
illustrate and explain hydrogen bonds and van der Waals' forces
write and name the formulas of ionic and molecular compounds, following simple IUPAC rules
identify and describe the properties of ionic and molecular compounds and metallic substances
describe how intermolecular forces account for the properties of ionic and molecular compounds and metallic substances
classify ionic, molecular, and metallic substances according to their properties
relate the properties of a substance to its structural model
explain the structural model of a substance in terms of the various bonds that define it
Modern chemistry is directly involved in the development of new materials. Depending on their intended applications, materials can now be synthesized according to very specific properties such as weight, resistance to heat, flexibility, malleability, and electrical conductivity. In order to synthesize a new material, it is often necessary to have an understanding of the electron arrangement, and thus the type of bonding, in the material. For students, a knowledge of the nature of bonding is important because these bonds are ultimately responsible for a substance's physical and chemical properties. This illustrative example emphasizes the nature of science and technology.
Students identify changes in the composition of materials and the structure of common objects. The evolution of the bicycle and the automobile are good examples to show how characteristics of materials, like being lightweight and rust-resistant, have improved the efficiency of these vehicles.
The above exploration may lead to the following question:
How does the nature of the bonds determine a material's properties?
Students predict and explain the different types of intramolecular forces and intermolecular forces for a given compound. They should use accepted models to illustrate these forces. The studied compounds should be named and represented according to established conventions.
Important work by scientists relating molecular structure to its properties can be emphasized in this area of study.
Students can research some modern materials such as composites, resins, alloys, and ceramics and relate the properties of these materials to the bonds.
This illustrative example suggests ways students can be led to attain the following learning outcomes:
STSE: 115-7, 116-4, 117-11
Skills: 213-6, 214-1, 214-3
Knowledge: 321-6, 321-10
Attitudes: 443, 439
distinguish between scientific questions and technological problems (e.g., distinguish between questions such as "What is the process of corrosion?" and technological problems such as "How can we prevent corrosion?")
analyse why and how a particular technology was developed and improved over time (e.g., analyse the development over time of electrochemical cells from large bulky devices to tiny cells)
describe and evaluate the design of technological solutions and the way they function, using scientific principles (e.g., describe the evolution of electrochemical cells using the redox theory)
analyse natural and technological systems to interpret and explain their structure and dynamics (e.g., analyse examples of systems such as hydrogen fuel cells, car batteries, and nickel-cadmium cells)
evaluate the design of a technology and the way it functions on the basis of a variety of criteria that they have identified themselves (e.g., evaluate the design and functioning of corrosion prevention technologies as they apply to the maintenance of bridges, ships, and other steel structures)
identify questions to investigate that arise from practical problems and issues (e.g., identify questions such as "How can corrosion of a pipeline be prevented?")
define and delimit problems to facilitate investigation (e.g., refer to a simple "research cell" before trying to explain a "grapefruit cell")
formulate operational definitions of major variables (e.g., provide an operational definition for anode and cathode)
carry out procedures controlling the major variables and adapting or extending procedures where required (e.g., test the predicted voltage of an electrochemical cell)
select and use apparatus and materials safely (e.g., put waste from a lead-containing electrochemical cell into a disposal container)
compare theoretical and empirical values and account for discrepancies (e.g., compare the theoretical and empirical voltage of a cell)
evaluate the relevance, reliability, and adequacy of data and data collection methods (e.g., evaluate the reliability of a cell's voltage as measured in a high school laboratory)
construct and test a prototype of a device or system and troubleshoot problems as they arise (e.g., construct an electrochemical cell to assist in explaining the cell's function)
evaluate a personally designed and constructed device on the basis of criteria they have developed themselves (e.g., assess an electrochemical cell using criteria like voltage produced and reliability)
identify and evaluate potential applications of findings (e.g., identify and evaluate alternative applications for existing cells, such as using car batteries for wheelchairs)
evaluate individual and group processes used in planning, problem solving and decision making, and completing a task (e.g., review, as a group, individual contributions to a team whose task it was to build an electrochemical device)
define oxidation and reduction experimentally and theoretically
write and balance half reactions and net reactions
compare oxidation-reduction reactions with other kinds of reactions
illustrate and label the parts of electrochemical and electrolytic cells and explain how they work
predict whether oxidation-reduction reactions are spontaneous based on their reduction potentials
predict the voltage of various electrochemical cells
compare electrochemical and electrolytic cells in terms of energy efficiency, electron flow/transfer, and chemical change
explain the processes of electrolysis and electroplating
explain how electrical energy is produced in a hydrogen fuel cell
Students often use electrochemical applications in their everyday lives. By studying the design and function of various electrochemical technologies, students will better comprehend the relationship between science and technology with regard to the progress, evolution, and many uses of electrochemical cell technology. Other electrochemical processes and applications such as corrosion, corrosion protection, and electrolysis can also be studied within this context. This illustrative example emphasizes the relationships between science and technology.
Students discuss the different uses of batteries they have observed in their daily life. Examples could include the use of batteries and electrochemical cells in cars, pacemakers, hearing aids, and electronic equipment. As well, differences in these batteries and cells, like rechargeable and alkaline cells, would be mentioned.
The above exploration may lead to the following question:
How can we increase the efficiency of electrochemical cells for use in our everyday lives?
Students manipulate and "dissect" several types of batteries and electrochemical cells. This would allow students to compare the internal structures and it would facilitate their ability to explain how each battery or electrochemical cell works in terms of electrochemical principles.
Students design and build an electrochemical cell with a predicted voltage.
Students are then encouraged to test the electrochemical cell for the predicted voltage and suggest possible ways to increase the cell's efficiency.
Students work in teams to report on the use of electrochemical cells in a variety of contexts. The teams would be expected to evaluate the appropriateness of these applications.
Students work collaboratively to design and build an electrochemical cell to power a small, motor driven device or a flashlight, and identify ways to maximize its efficiency.
This illustrative example suggests ways students can be led to attain the following learning outcomes:
STSE: 116-6, 116-7
Skills: 213-2, 213-8, 215-7
Knowledge: 322-4, 322-6
Attitudes: 440, 445
explain the roles of evidence, theories, and paradigms in the development of scientific knowledge (e.g., explain how bonding theory can help one understand certain colligative properties)
identify various constraints that result in tradeoffs during the development and improvement of technologies (e.g., identify industrial constraints where an increased yield is technologically feasible but not cost-effective)
compare processes used in science with those used in technology (e.g., compare stoichiometry used in both science and technology)
explain how a major scientific milestone revolutionized thinking
in the scientific communities (e.g., explain how Avogadro's hypothesis
revolutionized thinking in chemistry)
analyse and describe examples where scientific understanding was enhanced or revised as a result of the invention of a technology (e.g., identify examples such as the invention of analytical tools and techniques like mass spectroscopy and flame ionization, which have enhanced our understanding of the impurities found in our water systems)
analyse and describe examples where technologies were developed based on scientific understanding (e.g., provide examples such as a sensitive conductivity meter, which is used to determine concentration of ionic impurities in water and is based on ionic theory)
analyse society's influence on scientific and technological endeavours (e.g., analyse the public outcry that led to a ban on phosphates in detergents)
identify and describe science- and technology-based careers related to the science they are studying (e.g., identify careers in areas such as water treatment and analytical chemistry)
design an experiment identifying and controlling major variables (e.g., design an experiment to test the stoichiometric method, using a given reaction)
state a prediction and a hypothesis based on available evidence and background information (e.g., predict the mass of product formed, using stoichiometry)
develop appropriate sampling procedures (e.g., develop sampling procedures to test for dissolved oxygen in water)
implement appropriate sampling procedures (e.g., test community water supplies for dissolved solid levels)
use instruments effectively and accurately for collecting data (e.g., use a balance to measure mass of precipitate formed in a chemical reaction)
estimate quantities (e.g., estimate excess volume needed for a stoichiometry experiment)
compile and organize data, using appropriate formats and data treatments to facilitate interpretation of the data (e.g., compile and organize data from an analysis of community water supplies to assist in determining dissolved solid levels)
identify and explain sources of error and uncertainty in measurement and express results in a form that acknowledges the degree of uncertainty (e.g., compare the solubility of sodium chloride obtained in the lab with the accepted value, in order to account for any discrepancies)
explain how data support or refute the hypothesis or prediction (e.g., explain the differences between the predicted yield and the actual yield in an industrial process)
identify and correct practical problems in the way a technological device or system functions (e.g., identify problems such as the determination of correct masses in stoichiometric experimentations)
communicate questions, ideas, and intentions, and receive, interpret, understand, support, and respond to the ideas of others (e.g., present an oral report detailing a stoichiometric experiment done at school)
define molar mass and perform mole-mass inter-conversions for pure substances
describe the process of dissolving, using concepts of intramolecular and intermolecular forces
define the concept of equilibrium as it pertains to solutions
explain solubility, using the concept of equilibrium
explain how different factors affect solubility, using the concept of equilibrium
determine the molar solubility of a pure substance in water
explain the variations in the solubility of various pure substances, given the same solvant
use the solubility generalizations to predict the formation of precipitates
explain the effect of solutes on the melting point of solid water, using intermolecular forces
identify mole ratios of reactants and products from balanced chemical equations
perform stoichiometric calculations related to chemical equations
identify various stoichiometric applications
predict how the yield of a particular chemical process can be maximized
It is important for students to understand that most chemical reactions involve chemicals dissolved in a medium, such as water. Learning opportunities involving the nature of solutes, solvents, the mole concept, balancing equations, and stoichiometry enable students to better understand the nature of chemical reactions. This illustrative example emphasizes the nature of science and technology.
Students compare properties of different kinds of solutions using various technologies, and establish classes of solutions such as electrolyte/nonelectrolyte or acid/base).
The importance of controlling concentration can be illustrated by reminding students that a very low fluoride ion concentration is beneficial since it inhibits dental decay, but a concentrated fluoride solution is very toxic.
The above exploration may lead to the following question:
Why is the ability to predict the type and quantity of products in a reaction important for a scientific investigation or a chemical-industrial process?
Students perform calculations dealing with molar concentration of a solution, leading to the preparation of an ionic solution of known concentration. The use of appropriate equipment to prepare such a solution like a balance, volumetric flask, funnel, and beaker should be emphasized.
Students predict, using the method of stoichiometry, the quantity of reagent used or produced in a chemical system, given a specific quantity of another reagent used or produced in that reaction.
Students perform quantitative investigations to test the predictive ability of the stoichiometric method and quantitative analyses to determine an unknown quantity in a chemical system, such as the unknown concentration of a solution or the unknown mass of solute.
Students discuss with an industrial chemist the usefulness of the stoichiometric method in science and technology with a focus on the industrial applications.
This illustrative example suggests ways students can be led to attain the following learning outcomes:
STSE: 114-4, 114-7
Skills: 213-3, 214-12, 215-1
Knowledge: 323-10, 323-11
Attitudes: 439, 444, 445
describe the importance of peer review in the development of scientific knowledge (e.g., use examples such as the initial experiments in cold fusion conducted by Fleischman and Pons, which seemed to indicate a significant energy output, and the subsequent failure to achieve the same results in repetitions of the experiments, which led to the discrediting of the notion of cold fusion)
analyse and describe examples where technologies were developed based on scientific understanding (e.g., describe examples such as the development of racing fuels, lighters, propane stoves, and the Dewar flask)
analyse why scientific and technological activities take place in a variety of individual and group settings (e.g., analyse examples showing how many technologists, scientists, and agencies share their work on the determination of the heat content of foods, fuels, and explosives)
analyse the knowledge and skills acquired in their study of science to identify areas of further study related to science and technology (e.g., explain that the knowledge and skills related to calorimetry are essential to the training of a specialist in chemical engineering)
analyse from a variety of perspectives the risks and benefits to society and the environment of applying scientific knowledge or introducing a particular technology (e.g., analyse the risks and benefits of burning coal or other combustible materials to generate electricity)
distinguish between questions that can be answered by science and those that cannot, and between problems that can be solved by technology and those that cannot (e.g., state that science can predict the energy value of fossil fuels and that technology can develop methods to harness that energy, but that neither science nor technology can tell us the best use for valuable resources)
propose courses of action on social issues related to science and technology, taking into account an array of perspectives, including that of sustainability (e.g., compare emissions of greenhouse gases from a variety of sources and propose courses of action for their reduction)
design an experiment identifying and controlling major variables (e.g., design an experiment to determine calorimetrically an enthalpy change)
evaluate and select appropriate instruments for collecting evidence and appropriate processes for problem solving, inquiring, and decision making (e.g., use a calorimeter in heat transfer experiments)
use library and electronic research tools to collect information on a given topic (e.g., obtain information in a variety of ways on how much heat can legally be released into a lake or a river)
select and integrate information from various print and electronic sources or from several parts of the same source (e.g., obtain information of an economic nature on the best way to generate electricity in your region)
compile and display evidence and information, by hand or computer, in a variety of formats, including diagrams, flow charts, tables, graphs, and scatter plots (e.g., use a decision-making matrix to determine the best fuel to use for heating buildings in Canada)
apply and assess alternative theoretical models for interpreting knowledge in a given field (e.g., predict an enthalpy change and compare the experimental result with the predicted results in order to evaluate Hess's Law, the bond energy method, and calorimetry)
propose alternative solutions to a given practical problem, identify the potential strengths and weaknesses of each, and select one as the basis for a plan (e.g., identify strengths and weakness of the different ways to generate electricity)
identify multiple perspectives that influence a science-related decision or issue (e.g., decide on the best way to dispose of pollutants from an electrical generating plant, using economic, scientific, technological, ecological, and ethical perspectives)
work cooperatively with team members to develop and carry out a plan, and troubleshoot problems as they arise (e.g., carry out experiments to measure the heat used or produced in a variety of chemical reactions)
write and balance chemical equations for combustion reactions of alkanes
define endothermic reaction, exothermic reaction, specific heat, enthalpy, bond energy, heat of reaction, and molar enthalpy
calculate and compare the energy involved in changes of state and that in chemical reactions
calculate the changes in energy of various chemical reactions using bond energy, heats of formation, and Hess's law
illustrate changes in energy of various chemical reactions, using potential energy diagrams
determine experimentally the changes in energy of various chemical reactions
compare the molar enthalpies of several combustion reactions involving organic compounds
In Canada, many electrical power plants depend on the combustion of fuels such as coal, diesel, woodchips, and natural gas. As the production of energy and subsequent use of that energy costs money, there is a need to ensure an efficient process for producing and using energy. Students should be provided with opportunities to study the concept and issues of having heat to generate electricity. This illustrative example emphasizes the social and environmental contexts of science and technology and the unifying concept of energy.
Students compare different ways of producing electricity in Canada. Methods such as nuclear energy, hydroelectricity, wind energy, and other sources of energy will probably be mentioned, but the focus should be on the methods that use combustion reactions.
The above exploration could lead to the following question:
Which fuel is best to use in electric power plants?
Students should predict the amount of heat generated in a variety of combustion reactions using bond energies, heats of formation, and Hess's law. Their calculations leading to the predictions can be communicated graphically using potential energy diagrams.
Students carry out experiments using basic calorimetry to measure the heat used or produced in a variety of chemical reactions. They then compare their experimental results with their predictions.
Students visit a power plant to appreciate the scope and complexity of the technology involved. They could then associate their understanding to direct technological applications and potential careers.
Students prepare a report recommending the use of a particular fuel for a power plant. Their recommendation should take into account a comparison of the emission of greenhouse gases and other pollutants from the reactions. The report should also contain references to economic, scientific, technological, ecological, and ethical perspectives, as well as the issue of sustainability.
This illustrative example suggests ways students can be led to attain the following learning outcomes:
STSE: 117-9, 118-10
Skills: 213-7, 214-3, 215-4
Knowledge: 324-4, 324-6
Attitudes: 441, 446
Framework table of contents or Learning outcomes presented by grade or Next section or Title page