Course Profile Science, Grade 9 applied, Public

Unit 3

Course Profiles are professional development materials designed to help teachers implement the new Grade 9 secondary school curriculum. These materials were created by writing partnerships of school boards and subject associations. The development of these resources was funded by the Ontario Ministry of Education. This document reflects the views of the developers and not necessarily those of the Ministry. Permission is given to reproduce these materials for any purpose except profit. Teachers are encouraged to amend, revise, edit, cut, paste, and otherwise adapt this material for educational purposes.

Any references in this document to particular commercial resources, learning materials, equipment, or technology reflect only the opinions of the writers of this sample Course Profile, and do not reflect any official endorsement by the Ministry of Education or by the Partnership of school Boards that supported the production of the document.

Acknowledgments

Public District School Board Writing Teams – Science

Course Profile Writing Team

Arthur Prudham, Lead Writer, Waterloo Region District School Board and

Science Co-ordinators and Consultants Association of Ontario

Tom Card, Peel District School Board

Bob Callcott, York Region District School Board

Chuck Hammill, Peel District School Board

Heather Troup, Peel District School Board

Peter Tse, York Region District School Board

Contributing Writers (Unit 5)

George Huff, Fiona White, Allan Smith

Internal Reviewers

Dave Arthur, Ontario Society for Environmental Education (OSEE); Paulette Luft, Philip Marsh, Elaine Sturm, Peel DSB; Fiona White, Kawartha Pine Ridge DSB and STAO

Lead Board

Peel District School Board

Allan Smith, Project Manager

Partner Boards

Kawartha Pine Ridge District School Board, Ottawa Carleton District School Board, Waterloo

Region District School Board, York Region District School Board

Associations

Ontario Society for Environmental Education (OSEE)

Science Co-ordinators and Consultants Association of Ontario (SCCAO)

Science Teachers Association of Ontario (STAO)

Unit 3: Chemistry: Exploring Matter

Time: 22 hours

Unit Description

Students design and conduct investigations on the properties of elements and compounds with a focus on laboratory and environmental safety. The topics of the unit lend themselves naturally to experimentation and provide opportunities for students to collect, record, organize, and interpret data. A culminating activity for the unit addresses environmental concerns and health safety issues and relates to the production and use of common elements and compounds.

Strand(s) and Expectations

Strand(s): Chemistry

Overall Expectations: CHV.01, CHV.02, CHV.03

Specific Expectations: CH1.01 to 09; CH2.01 to .10; CH3.01 to .04

Activity Titles (Time and Sequence)

Activity 1	What is Chemistry?	105 minutes
Activity 2	Classifying Changes	240 minutes
Activity 3	Elements and Atoms	360 minutes
Activity 4	The Periodic Table	90 minutes
Activity 5	Compounds and Molecules	180 minutes
Activity 6	An Introduction to Qualitative Analysis	165 minutes
Activity 7	End-of-Unit Task	180 minutes

Prior Learning Required

Students should have some background knowledge of properties and changes in matter from Grade 5 and pure substances and mixtures from the Grade 7 curriculum. Until full implementation of the Grade 1-8 program, the amount of guidance, review and new teaching required in the activities changes from year to year. Students are familiar with some parts of the Particle Theory, changes of state, energy transformations, safe use of some apparatus and equipment, making observations, identifying variables, and designing and conducting controlled experiments or fair tests.

Unit Planning Notes

· Examine the end-of-unit task prior to the start of the unit to put the activities in context.

· Safety issues related to the use and disposal of chemicals as well as safe laboratory practices and the use of small quantities of chemicals wherever possible (both for economic and environmental reasons) must be stressed in all activities. The teacher should always model safe practices. Check that all chemicals to be used in the activities are sanctioned by the district school board, and if not, make substitutions or use alternative demonstrations. Solutions used for qualitative analysis should be prepared in well labelled dropper bottles and be of 0.1 mol/L concentrations. The containers can be reused simply by replenishing the solutions.

· Research is required for Activities 3 and 7. Collaborate with the teacher-librarian to acquire necessary resources and arrange for time in the library/resource centre or for resources to be brought to the science room. It is helpful for the teacher to accumulate a file for use in the science classroom when research is required. All suggested activities should be tried by the teacher before presenting them to the class.

A Note on Science Fairs

This unit provides opportunities for students to begin open-ended, experimental inquiry. When they have access to a science fair, students should be encouraged to present their findings there for a variety of reasons: preparation for a science fair requires self-assessment based on clearly-stated criteria; presenting to an alternative audience deepens understanding of the topic; judges are able to provide expert feedback on both process and product; and wider recognition of good work may motivate students to pursue further inquiry.

Teaching/Learning Strategies and Activities

Activity	Strategy	Description
1	Teacher demonstrations; discussion and safety plan development	Demonstration - dramatic changes in properties of chemicals (chemical reactions) leads into diagnostic assessment. Concepts of safety including WHMIS and expectations of the end-of-unit task are discussed.
2	Laboratory activities; experimental design	A series of activities to differentiate between chemical and physical change, followed by making and lighting of candles. A controlled experiment on the corrosion of metals is designed and performed.
3	Discussion; research inquiry; note making; observational activities	Ideas of atomic theories are introduced. Students research an assigned or chosen element and present their findings to the class.
4	Experimental inquiry	The organization of the periodic table is introduced. Students experimentally determine properties of metals and non-metals.
5	Model building; experimental inquiry	Concepts of compounds and molecules are introduced. Students compare properties of two compounds with similar formulae and build models of simple compounds.
6	Observational activities; guest speaker presentation	Students perform qualitative analysis to identify different ions. A guest speaker presents information on careers in chemistry.
7	End-of-unit task	Students work individually to identify unknown ions and complete research related to the uses and environmental concerns of the ions.

Assessment/Evaluation

Activity	Assessing and Evaluating	Method or Instrument
1	Laboratory rules; home application of safety rules	Quiz; review of notebooks to assess home safety plan (see Resources below)
2	Safe laboratory practices	Diagnostic checklist
	Laboratory skills	Diagnostic checklist
	Inquiry skills - experimenting (report on corrosion experiment)	Rubric
3	Communication skills; understanding concepts	checklist and quiz
	Research and communication skills (report on Elements)	Rubric
4	Safe laboratory practices	Checklist
	Laboratory skills	Checklist
	Basic concepts	Quiz and notebook check
5	Basic concepts (Models)	Marking scheme - peer and self
6	Communication skills	Rubric to assess Science Journal (see Resources below)
	Qualitative analysis	Self assessment
7	Inquiry skills	Rubric
	Research and communication skills	Rubrics
	Safe laboratory practices and skills	Checklists
	Basic concepts	Test

Resources

The Essential Science Course Profile, Appendix OV-2, is a rubric for assessing a science learning log. Although the learning log as defined there is a combination of a Science notebook and Science Journal as described in this profile, the criteria and levels of achievement descriptors would be very useful in creating rubrics for assessing and evaluating both Journals and notebooks. Also in that profile is a rating scale suitable for student use in assessing their own notebooks (Appendix OV-5, page 26). The Essential Science Profile, written by the Public and Catholic District School Board Partnership, is available on the Ontario Curriculum Clearinghouse web site at http://www.curriculum.org.

Chem 13 News Magazine. Ontario, Canada: Department of Chemistry, University of Waterloo.

Crucible. The magazine of the Science Teachers Association of Ontario, STAO. Dresden, Ontario.

(www.stao.org)

Liem, T.K. Invitations to Science Inquiry. 2nd edition. Paperback. Chino Hills: Science Inquiry Enterprises, 1990. ISBN 187810 621 X

Includes demonstrations for chemistry, physics, biology and Earth Science.

Scales of Scientific Inquiry and Technological Design. Peel District School Board, 1998.

Summerlin, L.R., C.L Borgford, and J.B Ealy. Chemical Demonstrations. A Sourcebook for Teachers. Volumes 1 and 2. Washington: American Chemical Society, 1988.

An excellent source for demonstrations; includes brief explanations regarding the chemical reactions involved. Available from: American Chemical Society, Distribution Office, Department 225, 1155 16th Street NW, Washington, DC 20036 1-800-227-5558

Web Sites

http://www.stao.org/safety.htm

Activity 1: What is Chemistry?

Time: 105 minutes

Description

This introductory activity has three purposes: to raise students’ interest in chemistry, to set the stage for the end-of-unit task, and to caution students about the importance of safety when working with chemicals.

Strand(s) and Expectation

Strand(s): Chemistry

Expectations: CH1.08, CH2.01, CH2.02, CH2.03.

Planning Notes

· The suggested demonstrations need preparation ahead of time. They are intended to be eye-catchers and the more dramatic the effects, the better. Using them as a natural lead-in, a discussion or a video on safety and Workplace Hazardous Material Information System (WHMIS) can follow. A number of school boards have ready-made videos on safety in the Science lab; reservations for those videos may be required.

· Activity 1.1 introduces the End-of-Unit task, Activity 7.

Prior Learning Required

Some knowledge of changes of state and physical and chemical changes from Grades 5 and 7.

Teaching / Learning Strategies

1.1 Student Activity: The students observe demonstrations of interesting phenomena featuring chemical and physical changes. They record observations in their Science notebooks describing evidence of chemical change, reactants and products, chemical and physical properties, and safety precautions. Students also record questions that come to mind for possible inclusion on the Wonder Wall. They make an entry in their Science Journal describing their understanding of what chemistry is.

Teacher Facilitation: Introduce the vocabulary of chemistry through demonstrations that include some dramatic changes in properties. Differentiate between observations and inferences, and emphasize the concept of repeatability/predictability of chemical reactions and the constancy of chemical properties of pure substances.

Some possible demonstrations are magnesium metal in hydrochloric acid (gas produced); copper wire in silver nitrate solution (new solid produced); attempting to ignite a small piece of paper dipped in water then in alcohol (different chemical properties of similar looking chemicals); mixing potassium iodide and lead (II) nitrate (colour change through solid produced); heating bimetallic strip (physical change - different rates of expansion); heating glass with the palm (physical change - expansion); dissolving ammonium nitrate in water (temperature change); diffusion of potassium permanganate in hot and cold water (physical property - different rates in diffusion); lava lamps, paraffin and kerosene mixture (physical change); collapsing plastic bottle (physical change - implosion); dextrose and methylene blue (blue bottle) demonstration (colour change), see Academic Profile, Unit 3, Activity 2.

Safety considerations are made explicit as the teacher performs the demonstrations so that students understand that safety is of utmost importance in the laboratory. Concern for the environment is stressed by using small quantities and proper disposal methods.

The teacher may find it necessary to deal with the misconception that all physical changes are reversible and all chemical changes are irreversible.

The teacher should also introduce the final task which is based on the repeatability and predictability of chemical reactions.

1.2 Student Activity: Students compare chemical warning symbols on common household products to WHMIS symbols on Material Safety Data Sheets, MSDS. They examine a list of safe laboratory procedures for their relevance and application at home and record their conclusions.

Teacher Facilitation: Provide MSD Sheets for some of the chemicals used in demonstrations. Labels of household cleaning products (e.g., detergent and other cleaning products, motor oil, medicines, white-out, glue and adhesives, etc.) should be provided. A set of safe laboratory practices should be prepared for distribution.

Assessment/Evaluation Techniques

A quiz to ensure student understanding of safe laboratory practices should be given prior to Activity 2. Several scenarios (visual, written, or teacher dramatization) depicting hazardous lab situations are presented to the students. The students then identify the incorrect procedure and describe remediations. Appropriate and clear strategies (e.g., storage, fire routes) for the safety plan can be assessed using the Achievement chart, Policy document, pp. 46-47.

Accommodations

It is possible that some students are allergic to common chemicals. Be aware and involve them in discussing the ideas without coming in contact with the chemicals. Where feasible, provide alternate chemicals for study.

Resources

Liem, T.K. Invitations to Science Inquiry. 2nd edition. Paperback. Chino Hills: Science Inquiry Enterprises, 1990. ISBN 187810 621 X

Includes demonstrations for chemistry, physics, biology and Earth Science. ISBN 187810 621 X

Summerlin, L.R., C.L Borgford, and J.B Ealy. Chemical Demonstrations. A Sourcebook for Teachers. Volumes 1 and 2. Washington: American Chemical Society. 1988.

An excellent source for demos; includes brief explanations regarding the chemical reactions involved. Available from: American Chemical Society, Distribution Office, Department 225, 1155 16th Street NW, Washington, DC 20036 800-227-5558

Video

Laboratory Safety: A Practice For Life. Available from STAO.

The Winning Label: A Simplified Introduction to WHMIS. Alberta Vocational College, Calgary.

Web Sites

http://www.stao.org/safety.htm

Activity 2: Classifying Changes

Time: 240 minutes

Description

The ideas of chemical and physical changes are differentiated in this activity through student investigation, and consolidated through the making and lighting of a candle. The four aspects of experimental design - initiating and planning, performing and recording, analysing and interpreting, and problem solving are explained and experienced in Activity 2.3.

Strand(s) and Expectations

Strand(s): Chemistry

Expectations: CH1.08, CH2.01, CH2.02, CH2.03, CH2.04, CH2.07, CH2.09.

Planning Notes

Equipment and materials needed for these activities are readily found in most Science labs. Test tubes of wax need to be prepared prior to the activity. Safety needs to be emphasized, as melted paraffin is very hot and can cause serious burns. An MSD Sheet for paraffin is needed. A demonstration of the safe use of Bunsen burners is required before Activity 2.1.

Prior Learning Required

· familiarity with the concepts of physical and chemical changes and changes of state

· knowledge of handling hot liquids and safe laboratory practices are important

Teaching/Learning Strategies

2.1 Student Activity: The students perform a series of activities to classify reactions as either physical or chemical changes. They record the observations in their notebooks and justify their classifications using the observations from the activities.

Teacher Facilitation: Set up a series of activities demonstrating chemical and/or physical change. Some possible activities include: heating of bimetallic strip (physical); mixing of 5.0 mL of alcohol with 5.0 mL of water (physical); heating of the ball and ring apparatus (physical); diffusion of potassium permanganate in hot and cold water (physical); the pushing a droplet of water and a droplet of alcohol on wax paper (physical); the air thermometer/palm glass (physical); baking soda in water (physical); Alka-Seltzer in water (chemical); starch in iodine (chemical); Benedict’s solution and sugar (chemical); baking soda in acid (chemical); bleach in ketchup (chemical); magnesium in dilute hydrochloric acid (chemical); crushing sugar cubes (physical); melting ice (physical); crystallizing supersaturated sodium acetate solution (physical).

2.2 Student Activity: The students make candles following a set of written instructions, then light them after the wax has solidified. They make observations before and after making and lighting the candles. They classify their observations as either physical or chemical changes/properties in their notebooks.

Teacher Facilitation: The making of candles demonstrates the reversibility of some changes. Caution students about the dangers of hot liquids and demonstrate the techniques required for handling the equipment. Have the MSD Sheet for paraffin in the classroom.

Melted wax must not be poured into sinks as it will block the pipes when cooled. Although cleaning the equipment while hot is possible, it might be simpler to reuse the set of test tubes. Prior to the laboratory activity, melt wax (from tea candles) in a beaker using a hot water bath. Pour the liquid paraffin into test tubes and let it solidify. During the activity, each student group can take a test tube, melt the wax using a hot water bath and pour the melted liquid into empty tea candle molds. Alternatively, students can bring containers from their homes. They can melt small pieces of crayon and/or add small amounts of essential oils to colour and scent their candles during the melting process. To prepare the wick, a small length of commercial wick material (available from craft stores) is dipped into the hot wax and then pulled taut with one end attached to a penny using the wax as glue. While the candles are solidifying, students make as many observations as possible in their notebooks and classify any properties/changes as either physical or chemical. When the candles have solidified, they are lit and the observation and classification processes are repeated.

2.3 Student Activity: In groups, students identify variables that affect corrosion and record them on a graphic organizer. Following a process modelled by the teacher, the students expand the organizer to include brief descriptions for how each variable might be manipulated in an experiment. They then select one variable and design a controlled experiment to test the effects of that variable on the corrosion process. The experimental design should include hypothesis, procedure to follow, materials required and method of recording. Once the design has been approved by the teacher, students carry out the experiment, record observations, analyze and interpret the data, and make a conclusion. They submit a report for evaluation.

Teacher Facilitation: Introduce the concept of corrosion and have students relate it to examples in their everyday life. Help the class develop a graphic organizer (web or bubble chart) to identify possible variables that affect the rate of corrosion. From this organizer, students choose variables to study and validate. Use the type of metal as the variable to show students how to develop a testable experimental question, and how to design a controlled procedure. The procedure should then ensure that the following items are held constant: quantity of metal; quantity and type of water and salt; and temperature - only the type of metal changes.

The discussion of controlled experimentation should include the development of hypotheses, number of trials, data collection and recording, analysis and interpretation of the data, and making conclusions based on evidence. Ensure that each group tests a different variable and take time at the end to pool class results for a discussion.

Distribute a handout describing the evaluation of this activity to the students prior to their conducting the experiment. As this is not a final evaluation, check the feasibility and safety aspects of the students design and redirect them as necessary. The observations may require up to a week to complete. Probes may be used where appropriate.

Assessment/Evaluation Techniques

· Diagnostic assessment of laboratory skills and safety procedures can be made using a checklist. In later activities, skills, and safety may be evaluated using the same checklist. The Corrosion Experiment reports may be evaluated using the Partial Rubric for Inquiry - Experimenting (TSM p. xi - Phase 1).

· Develop with the students a checklist to use in evaluating the graphic organizer.

Accommodations

Students with impaired motor skills may work with a partner.

Resources

Graphic Organizers (TSM p. iv - Phase 1)

Activity 3: Elements And Atoms

Time: 360 minutes

Description

This activity introduces students to elements, the simplest pure substance, and atoms, the smallest particles of an element. Students organize information about atomic theories, subatomic particles and Bohr-Rutherford diagrams. Working with a partner, they research one element and creatively present their findings to the class.

Strand(s) and Expectations

Strand(s): Chemistry

Expectations: CH1.01, CH1.03, CH1.04, CH2.05, CH2.06, CH3.01, CH3.02, CH3.03.

Planning Notes

Where possible avoid using elements which are used in Activity 7, as this would give some students an unfair advantage in the completion of their culminating task. Research time should be pre-arranged with the teacher-librarian. The research could be spread over several days with the actual presentations occurring after Activity 3.6.

Prior Learning Required

Students were introduced to the concept of atoms during Unit 1, Weird Water. Students have practised research skills earlier in the course but may need some guidance in the completion of research and the organization of information.

Teaching/Learning Strategies

3.1 Student Activity: The students recall some characteristics of pure substances and mixtures (Grade 7). They identify an element as the simplest form of pure substance and the building block of all other pure substances. Students review their understanding of atoms based on Unit 1, Activity 5- Phase 1. Students record information in their notebook.

Teacher Facilitation: Introduce the concept of an element by presenting students with examples of different elements they have encountered in their experiences: copper, silver, gold, oxygen, chlorine, etc. Ensure that students identify atoms as the smallest particles to which elements can be divided and that the different properties of elements result from differences in the structure of their atoms.

3.2 Student Activity: Students, working in pairs, select or are assigned an element to research focussing on properties, uses, and methods of obtaining and processing the element. Environmental concerns should also be addressed. The information obtained is to be presented in a creative format of their choice (e.g., poster, pamphlet, video, flip book, game show, T-shirt, web site, presentation program, etc.). Students also view and evaluate the presentations of others.

Teacher Facilitation: Prior to beginning the assignment, describe the requirements and the subsequent evaluation. Research could be arranged over a number of part periods and preparation of the display could be spread throughout the activity. Presentations then take place after completion of Activity 3.6. Organize the presentations so that one member of each pair stays with the display, explaining it to other students, while the other member moves from station to station at designated intervals. Students record information in their notebooks and evaluate each display using a rubric or rating scale. The roles of the partners are reversed and the whole process is repeated.

3.3 Student Activity: Students watch a video outlining the atomic theories of Dalton, Thomson, Rutherford and Bohr. As an alternative or supplement, students may read sections of their textbook and summarize the main ideas in their notebooks in chart form.

Teacher Facilitation: Review the idea of scientific models as discussed in Unit 1(Phase 1), emphasizing to students that theories and models evolve as more sophisticated observations are made. Then review the descriptions of the atomic theories once students have had the opportunity to complete their notes from video and text assignment.

3.4 Student Activity: Students complete a reading assignment about subatomic particles (protons, electrons and neutrons), their characteristics (relative mass, location, and charge), atomic number and mass number. Students answer questions and record information in their notebooks. Given atomic number and mass number for five different elements, students calculate the number of protons, electrons, and neutrons.

Teacher Facilitation: Introduce the reading assignment and check for completion and understanding. An analogy can be used to correct misconceptions student have about the relative size of the subatomic particles and space occupied by the atom (e.g., kernel of corn as the nucleus and the football field as the rest of the atom). Describe atomic number and mass number and show how these are used to calculate the numbers of protons, electrons and neutrons. Then assign five different elements (some beyond the first 20) so that students can practise their calculation skills. The teacher may want to introduce this activity by reviewing the Particle Theory (see Academic Profile for ideas).

3.5 Student Activity: Students use Bohr-Rutherford diagrams as a means of representing atoms and complete drawings for the first 20 elements.

Teacher Facilitation: Demonstrate Bohr-Rutherford diagrams for atoms with one, two and three energy levels. Once the rules for making the diagrams have been established, the teacher assigns the completion of the diagrams for the first 20 elements. The diagrams can be completed on the grid provided in the Attachment.

3.6 Student Activity: Students perform and record results of flame tests (i.e., colour of the flame produced by the burning of the compound). Once they have completed ten known samples, they repeat the flame tests with three unknowns A, B, and C, and determine the identity of each.

Teacher Facilitation: Introduce the flame test as an analytical tool for identifying some substances and review the safe use of Bunsen burners. Prior to students performing the flame test, explain how the input of energy raises electrons to a higher energy level and the return of the electron to a lower level is accompanied by the release of energy in the form of light. The quantity of energy released, and therefore the colour of light in the flame, is characteristic of the substance. Set up a series of flame test solutions. The following are suggested: two potassium compounds, two sodium compounds, two copper compounds, one of calcium, lithium, strontium and barium compound. Three of the previous solutions are set up as unknowns A, B, and C. Solutions are stored in small bottles with wooden splints soaking in each prior to burning. Caution the students not to burn the splints, only the solution (about 5 seconds) so the splints can be reused. Replenish the solutions and splints as required.

Notes:

1. The flame colour of sodium is so intense that it may shield other results, not only at a particular laboratory station, but often throughout the room. Suggest that students do all other tests first, and that no group perform the sodium test until all others are done.

2. Care must be taken that solutions are not contaminated by splints being transferred from one solution to another during the activity.

Assessment/Evaluation Techniques

Notebooks can be assessed for organization, completion and accuracy using a checklist. The Partial Rubric for Inquiry - Researching (TSM p. xii - Phase 1) and/or the Marking Scale (Rubric) for Written Report (TSM p. xiv - Phase 1) can be used for peer and teacher evaluation of the displays. Basic concepts could be evaluated by a quiz or test.

Accommodations

· Students with difficulty in perceiving colour may need to work with a partner in completing the flame tests.

· Students with impaired motor skills may work with a partner to complete the activities.

Resources

Videos

Atoms and Their Electrons. Burnaby B.C.: Classroom Video, 34 minutes.

Electron Arrangement and Bonding: Introducing the Players, The Rutherford-Bohr Model. Northey Productions.

Structure of the Atom Series: Smaller Than the Smallest, The Rutherford Model, The Bohr Model.

TVO videos.

Web sites

www.webelements.com

www.chemsoc.org/viselements/index.htm

Attachment: Blank Grid for Bohr-Rutherford Diagrams

1 Hydrogen							2

3	4	5	6	7	8	9	10

11	12	13	14	15	16	17	18

19	20	Instructions: Draw the Bohr-Rutherford diagrams for the atoms of each of the first 20 elements. Hydrogen has been done for you in box #1. Helium will be drawn in box #2, etc.

Activity 4: The Periodic Table

Time: 90 minutes

Description

The Periodic Table is introduced as a means of organizing elements into a chart that can provide useful information for chemists. Through teacher demonstrations and hands-on activities, students relate physical and chemical properties of a variety of elements to their position on the Periodic Table. Students also distinguish between metals and non-metals and identify their characteristic properties.

Strand(s) and Expectations

Strand(s): Chemistry

Expectations: CH1.05, CH1.06, CH1.09, CH2.01, CH2.04, CH2.06, CH2.08.

Planning Notes

Material needed:

· conductivity apparatus

· samples of metals, non-metals and metalloids

Each student should have their own copy of a simple Periodic Table so that families, periods and other information can be labelled. The teacher should set up the demonstrations ahead of time for the alkali metals. A video presenting information on the periodic table and properties of elements may be used.

Prior Learning Required

Reference is made to the Bohr-Rutherford diagrams drawn in Activity 3 (see Attachment for Activity 3). Students have some knowledge properties of elements from research.

Teaching/Learning Strategies

4.1 Student Activity: Students brainstorm organizational tools in their lives. They focus on the Periodic Table as a means of organizing more than 110 elements in a logical fashion. Through teacher demonstration, students link properties of selected elements to their position on the Periodic Table. Students then review their Bohr-Rutherford diagrams from Activity 3 and make connections between atomic structure and properties: members of the same family (vertical column) have the same number of electrons in their outer most energy level and members of the same period (horizontal row) have the same number of energy levels. Information from the class discussion and demonstrations are recorded in the notebook.

Teacher Facilitation: Initiate the brainstorming and relate this to the need to organize the information about elements. Demonstrate the similar physical and chemical properties of the alkali metals or the alkaline earth metals. Use a video to show the properties of other families such as the halogens or noble gases. Point out some features of the Periodic Table such as families and periods, and ensure that students can make connections between atomic structure and position on the table.

4.2 Student Activity: Students observe samples of metals, non-metals, and metalloids and record physical properties such as states at room temperature, melting and boiling point (from Periodic Table), conductivity, lustre, colour, malleability and ductility. The properties of these elements are related to their position on the Periodic Table. A graphic organizer is used to record properties of metals, non-metals, and metalloids.

Teacher Facilitation: Prepare kits that contain the equipment and small quantities of materials required for the tests. As an alternative, the equipment may be arranged by stations, but note that some tests require more time than others. In a follow-up discussion, show the location of the metals, non-metals, and metalloids on the Periodic Table and relate the observed properties of the elements to their positions.

Assessment/Evaluation Techniques

A checklist can be used to assess and evaluate the content of notes following discussions, demonstrations, and hands-on activities. Safe laboratory practices can also be evaluated with a checklist. Knowledge of basic concepts can be assessed through a test.

Accommodations

· Students with impaired motor skills may work with a partner.

Resources

Web Sites

http://www.liv.ac.uk/Chemistry/links/refperiodic.html

http://www.uky.edu~holler/periodic/periodic.html

http://PeriodicTable.com

Activity 5: Compounds and Molecules

Time: 180 minutes

Description

This activity introduces students to the other type of pure substance - compounds - and to the relationship between elements and compounds as well as atoms and molecules. The idea of models is extended to molecules and the concept of using a formula to represent the name of a compound is taught.

Strands and Expectations

Strand(s): Chemistry

Expectations: CH1.02, CH1.03, CH1.07, CH2.01, CH2.06, CH2.10.

Planning Notes

Materials required:

· ingredient lists for food products

· Hoffman apparatus for the electrolysis of water (either as teacher demonstration or for groups of students to perform)

· molecular model kits and other materials with which to build models (e.g., modelling clay, toothpicks, straws, foam balls)

· 3% hydrogen peroxide (purchased at any pharmacy, stored in the refrigerator)

Prior Learning Required

· Bunsen burners were used in previous activities but safety issues related to their use by students should be reviewed.

· Students described a model of the water molecule in Unit 1 and have knowledge of elements and atoms from Activity 3.

Teaching/Learning Strategies

5.1 Student Activity: Students listen to a list of ingredients read from two or three different food labels or other household products and try to predict the identity of the product. Students then guess the function of the compounds in these products. Wonder Wall questions may evolve from the discussion.

Teacher Facilitation: Use this activity to pique interest and illustrate the commonplace use of compounds in students’ lives. Find appropriate ingredient lists for this activity (e.g., from instant pudding, cool whip, peaches and cream oatmeal, plum sauce, moisturizing lotion, ice cream).

5.2 Student Activity: Students review the concepts of elements and atoms. Through teacher-led discussion, these concepts are extended to include the combination of elements in simple whole number ratios to form compounds and the nature of compounds as pure substances. Students observe the combustion of magnesium to illustrate the formation of a compound (magnesium oxide) from its elements. They then perform the electrolysis of water to show the decomposition of a compound into its elements. Following a safety demonstration, students use splint tests to detect oxygen (glowing splint) and hydrogen (burning splint).

Teacher Facilitation: Help students make connections between their previous knowledge of elements and the new concept of compounds. Demonstrate the electrolysis apparatus and safe testing for gases (oxygen and hydrogen). Stress the difference in properties of the compounds and their component elements. Small quantities of sulfuric acid need to be added to the water to ensure successful electrolysis.

5.3 Student Activity: Students compare the reaction of manganese dioxide with water and with 3% hydrogen peroxide (same quantities). Students record observations from before and after the reactions and determine the identity of any gas produced using the splint tests from Activity 5.1. Students predict the identity of any other product.

Teacher Facilitation: Introduce the activity by providing the formula of hydrogen peroxide (H₂O₂) from the label, MSD Sheet, name, etc. and comparing it to the formula of water. Following the experiment, emphasize how two compounds with very similar formulae have different properties. Extensions can include a consideration of the storage of hydrogen peroxide in the home, the role of catalysts, and comparisons of carbon monoxide and carbon dioxide. Students are encouraged to add questions to the Wonder Wall.

5.4 Student Activity: The students brainstorm examples of simple compounds and their formulae. From the examples, the students predict the structure of, and build, five molecules using modelling clay, toothpicks or other suitable material. Students then construct models of the same molecules using model kits and compare the currently accepted model with their predicted one. They describe their comparisons in their notebooks.

Teacher Facilitation: Record on the blackboard or chart paper the compounds and formulae suggested by the students (e.g., H₂O, H₂O₂, CO₂, CO, NH₃, CH₄, O₂, H₂, CH₃OH). As students make their predictions of the structure of the molecules, monitor the class and offer assistance and encouragement as needed. Then provide model kits, review the parameters of construction (e.g., all holes must be filled), and have students construct models of the compounds, comparing them to their predictions. Students are encouraged to add questions to the Wonder Wall.

Assessment/Evaluation Techniques

Models are peer- or self-assessed for accuracy.

Accommodations

· See TSM - Accommodations for Students with Special Needs (page i - Phase 1). Students with impaired motor skills can make observations while their partner performs the laboratory activity.

Activity 6: An Introduction to Qualitative Analysis

Time: 165 minutes

Description

Chemical reactions are important tools for identification of unknown substances. Students perform qualitative tests to establish a testing protocol and collect data to be use in the end-of-use task. Students are introduced to careers in analytical chemistry through a guest speaker and/or a video.

Strand(s) and Expectations

Strand(s): Chemistry

Expectations: CH1.08, CH2.01, CH2.06, CH2.07, CH3.04.

Planning Notes

All of the chemicals required for these qualitative tests should be in clearly labelled dropper bottles. The ions being tested should be labelled in one colour and the chemicals used to analyse should be labelled in another colour. The concentrations of the solutions should be 0.1 mol/L. Positive ion solutions should be made from the nitrate salts; negative ion solutions should be made from the sodium salts. Each group should have a complete set of bottles so that the students can proceed carefully at their own pace. The reactions should take place in spot plates or small test tubes, only five drops of each solution should be used in any test, and all wastes should be disposed of properly.

Prior Learning Required

Students need to be able to follow instructions carefully and to make observations and detailed records in their notebooks.

Teaching/Learning Strategies

6.1 Student Activity: The students conduct qualitative tests for the presence of the following positive ions: barium, silver, lead(II), copper(II), iron(III), aluminum, zinc, calcium and ammonium. They also conduct tests for the following negative ions: chloride, sulfate, phosphate, and carbonate. Within a separate section of the Science notebook, students record their observations for use later in the end-of-unit task. This section of the notebook will require a separate title page, date of data entry, index, tests for the ions, results and meanings of the tests. A spreadsheet may be developed as an alternative. It is important that all students complete these activities as the information is needed for the final tasks. Students should confirm their results with other groups and, if needed, repeat the test to ensure consistent, accurate results. Students should copy the results of their flame tests into this section of their Notebooks.

Teacher Facilitation: Provide the chemicals and equipment for each group, and review laboratory techniques and safety procedures (e.g., the need for clean equipment, use of spot plates and small amounts of chemicals, goggles, safe disposal and good ventilation in the laboratory). To prevent contamination of stock solutions, make sure the tips of the medicine droppers do not come in contact with the solutions to be tested.

Test for the presence of :

· silver and lead(II) ions, add HCl(aq). If a white precipitate forms, lead(II) or silver ions are present. Add NH₄OH(aq). If the precipitate dissolves silver ions are present. If it doesn’t, lead(II) ions are present.

· iron(III) and aluminum ions, add NH₄Cl(aq) and NH₄OH(aq). If a rust brown precipitate forms, iron(III) ions are present. If a white precipitate forms, aluminum ions are present.

· copper(II) ions, observe a pale blue colour or add NaOH(aq). If a bright blue jelly-like precipitate forms, copper(II) ions are present.

· zinc and nickel(II) ions, add NH₄Cl(aq), NH₄OH(aq) and Na₂S(aq) (in a fume hood). If a white precipitate forms, zinc is present. If a black precipitate forms, nickel(II) is present.

· barium and calcium ions, add NH₄Cl(aq), NH₄OH(aq), and (NH₄)₂CO₃(aq). If a white precipitate forms, calcium or barium ions are present. Add K₂CrO₄(aq). If a yellow precipitate forms, barium ions are present. If a yellow solution forms, calcium ions are present.

· ammonium ions, add NaOH(aq) and heat gently. If a gas forms which turns red litmus blue, ammonium ions are present.

· chloride ions, add AgNO₃(aq). If a white precipitate forms, chloride ions are present.

· carbonate ions, add HCl(aq). If fizzing occurs, carbonate ions are present.

· sulfate ions, add HCl(aq) and CaCl₂(aq). If a white precipitate forms, sulfate ions are present.

· phosphate ions, add FeCl₂(aq). If a precipitate forms, phosphate ions are present.

The teacher should check that all the chemicals mentioned above are sanctioned by their district school boards; if not, substitutions must be made. Similar tests are found in most senior chemistry textbooks.

6.2 Student Activity: Students participate in a discussion of careers involving analytical chemistry. Students write a reflection piece in their Science Journals related to the topic presented by the guest speaker or video.

Teacher Facilitation: The teacher may arrange for a video or guest speaker. Some topics include: forensics, quality control, mining, food science, medical technology, etc.

Assessment/Evaluation Techniques

Self- and peer-assessment of qualitative analyses for consistency. Evaluation of a reflection piece in the Science Journal for communication skills (see TSM page xiv - Phase 1). A checklist may be used to evaluate safe laboratory procedures.

Accommodations

· See TSM - Accommodations for Students with Special Needs (page i - Phase 1).

· Students with impaired motor skills can make observations while their partner performs the laboratory activity.

Activity 7: End-of-Unit Task

Time: 180 minutes

Description

Students role play as analytical chemists examining water samples for contaminants. They prepare a report outlining their findings, related environmental hazards, methods of rectifying the problem and reclaiming the contaminants.

Strand(s) and Expectation

Strand(s): Chemistry

Expectations: CH2.01 to 07, CH3.01 to 03.

Planning Notes

The teacher prepares water samples and scenarios. Each student analyses their own sample, but each sample (i.e., unknowns 1 to 30) need not be different.

Prior Learning Required

Students refer to Activity 6, results of the flame tests, and resources accessed in Activity 3.

Teaching/Learning Strategies

7.1 Student Activity: Students are presented with a scenario where they act as analytical chemists to complete a water analysis. The water samples contain not more than two possible ions. Each student designs their own testing protocol based on previous activities, using a flow chart or other graphic organizer. Reference should be made to their notebooks - special section, Activity 6. Students record results of their tests and draw conclusions based on those results. Students determine the source of contaminant from a list of possible industries supplied by the teacher. Student research focusses on the uses of the substance in the industry, health, safety, and environmental concerns, and methods of reclaiming the contaminants. Students, in role, prepare a report to the industry regarding their water analysis.

Teacher Facilitation: Water samples, equipment and list of industries must be arranged prior to the activity. Co-ordination with the teacher/librarian to facilitate the research process may be done ahead of time. Some samples of ions and related industries are: lead for batteries and solder, copper for electroplating and plumbing, barium for X-rays, zinc for galvanizing, silver for photography, iron for steel, aluminum for tin can production, phosphates for detergents and fertilizers, ammonium for fertilizers and explosives.

7.2 Student Activity: Students read their Journal entry from Activity 1.1 and complete a follow-up entry describing how their knowledge and understanding of chemistry has changed after completing the unit.

Teacher Facilitation: The teacher uses the final Journal entries as one method of assessing the effectiveness of the unit in broadening students understanding of chemistry. This could be used as part of the Course Evaluation.

Assessment/Evaluation Techniques

Final products can be evaluated using Rubrics for Inquiry - Experimenting and - Researching, Marking Scale (Rubric) for Written Report (pp. xi to xiii - Phase 1). The final Journal entry can be assessed for communication skills. A test or quiz can be given to assess understanding of basic concepts. The quality of the graphic organizer used could be evaluated using the checklist developed in Activity 2.

Accommodations

Teachers may have to assist some students with the completion of the lab. More time may be given and oral reports may be evaluated instead of the written form.

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