Course Profile Science, Grade 10, Applied,
Public
Unit 1: Chemical Reactions and Practical Applications
Time: 24 hours
Activity 1 | Activity 2 | Activity 3 | Activity 4 | Activity 5 |
Activity 6 | Activity 7 | Activity 8 | Activity 9 | Activity 10
Students conduct investigations to understand chemical reactions encountered in their everyday lives with a focus on laboratory and environmental safety. Experiments provide opportunities for students to collect, record, organize, and interpret data as well as to describe the reactions studied using models and equations. Activities are linked through the theme of acids and bases. In the end-of-unit task, students evaluate the effectiveness of antacids.
Strand(s): Chemistry
Overall Expectations: CHV.01P, CHV.02P, CHV.03P.
Specific Expectations: CH1.01P, CH1.02P, CH1.03P, CH1.04P, CH1.05P, CH1.06P, CH1.07P, CH1.08P, CH2.01P, CH2.02P, CH2.03P, CH2.04P, CH2.05P, CH2.06P, CH2.07P, CH2.08P, CH2.09P, CH3.01P, CH3.02P, CH3.03P, CH3.04P.
|
Activity 1.1 |
Introduction |
190 minutes |
|
Activity 1.2 |
Testing pH |
100 minutes |
|
Activity 1.3 |
Making acids and bases by synthesis |
150 minutes |
|
Activity 1.4 |
Making bases by displacement reactions |
150 minutes |
|
Activity 1.5 |
Acid/base neutralization – a double displacement reaction |
150 minutes |
|
Activity 1.6 |
Designing a Consumer Product |
150 minutes |
|
Activity 1.7 |
Complete and Incomplete Combustion |
100 minutes |
|
Activity 1.8 |
Design an Experiment: Pop the Lid |
150 minutes |
|
Activity 1.9 |
The Name Game |
100 minutes |
|
Activity 1.10 |
Antacid Analysis |
200 minutes |
· Lab safety procedures from Grade 9
· Understanding of chemical symbols and periodic table from Grade 9
· Chemical and physical change concepts from Grade 9
· Some understanding of designing an experiment, controlling variables and writing a lab report from Grade 9 and earlier
· Research and presentation skills from a variety of other courses
· Read through all the activities to review safety procedures, equipment, and materials required.
· Determine the approach to note making, group work, lab activities, and reports for the unit in order to establish clear standards and routines for students for this unit, especially since it establishes the tone for the whole course.
· Review the Teacher Support Materials (TSM) on Science Communication Skills.
· Consult with the teacher-librarian for assistance in gathering resources to be used.
· Start collecting samples and containers of antacids.
· Review chemical nomenclature and prepare to introduce the concepts in the context of the reactions studied, not as a separate topic. Students can then build up a repertoire of names of common compounds and then determine patterns of nomenclature towards the end of the unit.
· Review the career assignment in Activity 1.1.4 and determine how the time for it fits into the unit.
· Consult with the Guidance Department for assistance and resources with the career assignment.
· Consider inviting a guest speaker or panel to talk about careers related to this unit. Depending on your community, you could invite a lab technician from a local factory in the food and drug industry, community college professor or student from a chemical technology related program, a health and safety officer from other industries, or a pharmacy assistant from the local pharmacy.
|
Activity |
Strategy |
Description |
|
1.1: Introduction |
Co-operative learning, lab activity |
Students carry out a preliminary investigation of antacids and begin a career activity. |
|
1.2: Testing pH |
Lab activity, class discussion |
Students measure pH of a variety of household substances using paper indicators as well as probes. Class discussion consolidates concept of pH and acids and bases. |
|
1.3: Making acids and bases by synthesis |
Lab activity and teacher demonstration, class discussion |
Synthesis reactions between oxygen and metals and non-metals are investigated and the products tested for pH. Students are introduced to chemical equations. |
|
1.4: Making bases by displacement reactions |
Lab activity, teacher demonstration, class discussion |
Single displacement reactions between metals and water are investigated as a means of producing bases. Understanding of equations is consolidated. |
|
1.5: Acid/base neutralization - a double displacement reaction |
Lab activity |
Students perform a neutralization reaction, investigate the products, and write a lab report. |
|
1.6: Designing a Consumer Product |
Lab activity, production of an advertisement |
Students use a neutralize reaction to produce soap, individualizing it with added ingredients, and produce an advertisement for it. |
|
1.7: Complete and Incomplete Combustion |
Lab activity |
Students produce and investigate the combustion of acetylene. |
|
1.8: Design an Experiment: Pop the Lid |
Experimental design |
Students investigate rates of reaction by designing an experiment to pop the lid from a film canister in a specified time using the reaction between baking soda and vinegar. |
|
1.9: The Name Game |
Student review of chemical compounds from unit, game |
Review and consolidation of skills in naming chemical compounds using a bingo style game |
|
1.10: Antacid Analysis |
Student-designed lab activity |
Students use their knowledge of acids and bases and lab skills to test the effectiveness of different kinds of antacids. |
|
Activity |
Task |
Tool |
Links to Achievement Chart or Learning Skills |
|
1.1: Introduction |
Concept map |
Diagnostic, anecdotal only |
Inquiry, Making Connections Teamwork |
|
1.2: Testing pH |
Data table and pH line |
Checklist |
Knowledge/Understanding Teamwork |
|
1.3: Making acids and bases by synthesis |
Observation charts and equations, lab performance |
Checklists |
Knowledge/Understanding, Thinking/Inquiry Work habits |
|
1.4: Making bases by displacement reactions |
Lab safety performance, pre-lab quiz, procedure diagrams |
Checklists |
Knowledge/Understanding, Thinking/Inquiry, Communication |
|
1.5: Acid/base neutralization - a double displacement reaction |
Lab report |
Rubric |
Thinking/Inquiry, Communication |
|
1.6: Designing a Consumer Product |
Pre-lab safety quiz, advertisement |
Checklist, rubric |
Knowledge/Understanding, Communication, Making Connections |
|
1.7: Complete and Incomplete Combustion |
Observation charts and conclusions |
Rubric |
Knowledge/Understanding, Communication |
|
1.8: Design an Experiment: Pop the Lid |
Method design, performance |
Rubric, time check |
Thinking/Inquiry Teamwork |
|
1.9: The Name Game |
Quiz |
Marking scheme |
Knowledge/Understanding |
|
1.10: Antacid Analysis |
Method design, advertisement |
Rubric |
Knowledge/Understanding, Thinking/Inquiry, Communication, Making Connections |
Periodic table and extensive
information on elements
http://www.webelements.com
Extensive listing of journals of
interest to chemical educators
http://www.umsl.edu/~chemist/books/journals/journals.html
Chemical Institute of Canada site
– provides links to a variety of other Canadian organizations and could be
useful for careers and industry information.
http://www.chem-inst-can.org
American Chemical Society -
provides links to a variety of chemical sites and education resources.
http://www.acs.org/index.html
Chemical Industry Home Page –
useful for career and industry related information
http://www.neis.com/associations.html
Chemical Industry Research Help
http://www.iceman.org/ereschem.htm
Online Product Development
Resource
http://www.pdlab.com/welcome.htm
General Chemistry Online
http://antoine.frostburg.edu./chem./senese/101/index.shtml
Lab activities site with links to a
variety of labs done in this unit, as well as information for the final
activity
http://users.erols.com/merosen/labs.htm
Percival, S. and R. Wilson. Chemistry,
a Human Venture. Toronto: Irwin Publishing, 1988.
ISBN 0-7725-1696-0 (good basic coverage for those wanting to review basics of
chemistry)
Slater, Alan and G. Rapier-Canham. Microscale
Chemistry Lab Manual. Addison-Wesley,1994.
ISBN 0-201-60216-4, (Teachers’ Guide) ISBN 0-201-60215-6
Chem13 News. Published nine times per year by Department of Chemistry, University of Waterloo, Waterloo, ON N2L 3G1 (519-888-4567 Extension 2505)
Journal of Chemical Education. Available from Publishers Information Center, P.O. Box 606, Vineland, NJ 08360 (610-250-7264)
ChemMatters. Student magazine with lots of ideas for making chemistry relevant
for students. Comes with an excellent teachers’ guide. Index and more
information on ordering available at
www.acs.org/education/curriculum/tgindex.html
Time: 190 minutes
This activity introduces students to the course, to the chemistry unit, and to the end-of-unit task, stressing the importance in science of inquiry, communication, and making connections to the world in which we live.
Strand(s): Chemistry
Specific Expectations
CH1.06P - demonstrate an understanding of neutralization through investigation of simple acid-base reactions;
CH2.02P - through investigations and applications of basic concepts formulate scientific questions about acid-base neutralization reactions and outline experimental procedures to answer the questions;
CH2.04P - through investigations and applications of basic concepts select and integrate information from various sources, including electronic, print, and community resources, to answer the questions chosen;
CH3.02P - investigate applications of acid-base reactions in common products and processes;
CH3.03P - relate chemical reactions to familiar processes encountered in everyday life and identify careers that require knowledge of such processes.
· Collect a variety of antacid products, including some that are empty containers or packages.
· Review the TSM from the Grade 9 Essential Science Course Profile on co-operative learning.
· Prepare the materials for the activities.
This introductory activity assesses prior knowledge of acids and bases.
1.1.1 Student Activity: In small groups students create a concept map recording what they know collectively about acids and bases. They then participate in a class discussion about acids and bases and make summary point-form notes.
Teacher Facilitation: The teacher introduces the activity by emphasizing the importance of collaboration in science and reviewing co-operative learning skills. The teacher provides direction on the use of a concept map (see TSM 1B: Note-taking Styles) and starts one as an example. The teacher provides several focus questions to start: When is the word acid used in everyday language? When is it used in advertising? When we use the word “acid” or “acidic” as an adjective e.g., (acid taste, acid wit), acidic smile, what quality do we have in mind? What things get tested for acid content? The teacher may also assist individual groups with further questions such as: What things do you know are acids? What foods are acids? What are acids used for? The teacher leads a discussion about acids and bases and provides direction for point-form notes. The teacher demonstrates a molecular model of a water molecule, showing that it can be split into a hydrogen ion and a hydroxyl ion and explaining that when acids form there are more hydrogen ions in solution, and that when bases form there are more hydroxyl ions.
1.1.2 Student Activity: In small groups students examine a range of antacid containers and packages. They develop a data table to record the product, its state, the active ingredients, and the recommended dose. They then make a summary statement about what ingredients are in antacids and formulate questions about how they work. Each group then tests one antacid product with litmus paper and enters the data in a class data table. They also test the product by adding a small amount of dilute acid to the substance in a spot plate and describing the chemical reaction that occurs.
Teacher Facilitation: The teacher introduces the activity by asking the question “How do antacids work?” and discussing the need to first gather information. The teacher provides each group with a different set of antacids (either the packages themselves or a photocopied collage of labels) and assists students in developing a data table. The teacher gives each group a different sample (those receiving tablets need to be shown how to grind a portion and dissolve it in water to test it), and outlines the safety precautions for testing the reaction with acid. The teacher also reminds students about the importance of asking questions in science (including questions such as “What happens if?”) and of making careful observations.
1.1.3 Student Activity: Students review the end-of-unit task, in which they carry out a more detailed investigation of an antacid, and identify the need to learn more about acids, bases, chemical compounds, and reactions before they carry out the investigation. They set up a chemical log with three separate sections: Acids and Bases, Chemical Compounds, and Chemical Reactions. They set up a T-chart for Acids and Bases and summarize the information that they know. For chemical compounds they set up a T-chart for names and symbol names, and record the names of compounds listed as ingredients of antacids.
Teacher Facilitation: The teacher provides details on the end-of-unit task, including the rubric which is used for evaluation, and stresses the importance of learning more about the chemistry of acids and bases and reactions first. The teacher provides instructions for the chemical log as a way of keeping a summary of the new information they encounter. Opportunities are provided in each activity to update the log, and the information is used in later activities. The chemical log could also be combined with a response journal. (See TSM 1A: The Response Journal.)
1.1.4 Student Activity: Students participate in a class discussion on careers available in science, especially chemistry, and review an assignment on investigating a particular chemical related career. Later in the unit students choose a career to investigate. They produce a small poster outlining a description of the career, the education required, and the courses required at the high school level to be displayed on the Futures/Career Wall.
Teacher Facilitation: The teacher introduces the assignment with reference to career materials displayed in the classroom and on the Futures/Career Wall and examples of career possibilities. (See TSM 4.) The teacher advises students that they will choose a career to investigate in a few days, and have the remainder of the unit to prepare their poster.
|
Task |
Tool |
Category |
Learning Skill |
|
Concept map |
Diagnostic, anecdotal comments |
Knowledge, Inquiry |
Teamwork |
|
Antacid Table and Notes |
Checklist |
Inquiry, Communication |
Work habits |
· Provide a prepared data table or assist students with organizing an appropriate table.
· As an extension, have students bring in packaging for other products and identify names of simple compounds listed in the ingredients to add to their chemical log.
Time: 100 minutes
This activity allows students to become familiar with the concept of pH by measuring the pH of household substances that they use in their homes. The concept of pH is an important one for students to understand and use in the end-of-unit task and the final unit.
Strand(s): Chemistry
Specific Expectations
CH1.05P - classify substances as acids, bases, or salts based on their characteristic properties;
CH1.07P - describe how the pH scale is used to identify the concentration of acids and bases;
CH2.01P - through investigations and applications of basic concepts select and use appropriate handling, storage, disposal, and recycling of laboratory materials;
CH2.04P - through investigations and applications of basic concepts select and integrate information from various sources, including electronic, print, and community resources, to answer the questions chosen;
CH2.07P - use the pH scale to determine the acidity or basicity of some common household substances.
· Review safety procedures required and ensure there are safety goggles for each student.
· Prepare the materials required, with a range of materials for testing pH including probeware and spot plates. One strip of pH paper can be cut into four or five smaller pieces to cut down on the quantity of paper needed, especially if each student is working individually.
· Consider having students bring in a variety of products that can be safely transported from their homes to use for the lab or collect materials yourself. Up to twenty samples could be used depending on availability of products and the time that you wish to spend on this activity. This ensures that you have a good cross section of pHs represented.
· Numbers should be put on each item and the names recorded on the board to ensure that students test all of the materials.
· Distribute items around the classroom so that students are not cramped together while performing the activity. Keep the materials in a container so they are available for the next class. It is necessary to have a labelled glass rod for each substance tested to prevent cross contamination of materials.
· Consider using or demonstrating natural pH indicators such as red cabbage or cranberries.
· Grade 9 Chemistry concepts: elements and compounds, symbols, and formulae
· Handling chemicals safely and properly
1.2.1 Student Activity: Students participate in the class discussion on measuring pH. They develop a data table (possible headings for the data table could be: Prediction, Substance, pH, Acid or Base, Weak or Strong) and then work in pairs using pH paper strips laid out on a spot plate labelled with the name or number of the household substance being tested. They place a drop of the substance on its own pH strip that can be dried and attached as evidence of their results. Each pair measures one substance using the probe or meter and records it in a class data table as a secondary source of evidence.
Teacher Facilitation: The teacher leads a discussion on measuring how strong acids and bases are, using a demonstration of litmus paper with some sample materials and then using the pH indicator paper. The teacher introduces the pH scale, explaining both that a stronger acid has a lower pH and that a single unit difference indicates that it is ten times stronger or weaker (i.e., has ten times higher or lower concentration of H+ ions). The teacher then provides direction for the lab exercise, including outlining safety precautions. The teacher also demonstrates the use of pH probes or meters, if available, and takes turns with lab pairs showing how to use them
1.2.2 Student Activity: Students participate in a discussion about the results and then transpose the data onto a linear scale (ranging from 0 to 7 to 14) indicating pH values, recording the names of the substance in the appropriate spot. They answer questions or make summary notes.
Teacher Facilitation: The teacher leads the discussion, including reference to the information from different technologies for measurement, which allows students to recognize the accuracy and limits, leading to a discussion of how technology is important in increasing our knowledge. (Students should also become aware of the fact that even though a piece of equipment is supposed to be accurate it does not always give accurate results if the person using it is not familiar with its use.) The teacher also asks questions about any patterns in the substances that have similar pH readings. The teacher introduces the pH scale by talking about the variety of ways in which information is communicated in the course (see TSM 1B), emphasizing graphical as well as textual communication. The teacher demonstrates the pH scale, adding one or two examples, and provides students with summary questions. This line helps students see graphically how different substances having similar uses also have similar pH.
1.2.3 Student Activity: Students update the acids and bases section of their chemical log.
Teacher Facilitation: The teacher reminds them to include information relating to the properties of acids and bases.
|
Task |
Tool |
Category |
Learning Skill |
|
Data table and pH line |
Checklist |
Knowledge |
|
|
Lab work |
Rubric (from Grade 9 TSM) |
|
Teamwork |
· Provide a prepared data table for exceptional students or assist them with organizing an appropriate table.
Rayner-Canham, G. Chemistry, A First Course - Lab Manual. Addison-Wesley Publishers, 1988.
Time: 150 minutes
This activity introduces students to synthesis reactions as one method of producing an acid and a base in the lab. They burn a metal and non-metal, dissolve the end product produced in water, and determine the type of solution that has been synthesized. Practice in writing equations is started in this activity.
Strand(s): Chemistry
Specific Expectations
CH1.02P - demonstrate an understanding of chemical reactions, including conservation of mass, and their representation through balanced chemical equations;
CH1.03P - describe, using their observations, the reactants and products of a variety of chemical reactions, including synthesis, decomposition, and displacement reactions;
CH1.08P - name and write the formulae for common ionic and molecular compounds;
CH2.01P - through investigations and applications of basic concepts select and use appropriate apparatus, and apply WHMIS safety procedures for the handling, storage, disposal, and recycling of laboratory materials;
CH2.09P- represent simple chemical reactions using word equations, balanced chemical equations, and where appropriate, molecular models.
· Students must wear safety goggles during this experiment.
· Teacher should feel comfortable with the procedure before allowing students to do it.
· There are many skills required of the students to successfully complete this lab. The teacher must spend the necessary time going over and demonstrating the techniques that the students use as well as safety concerns. If the teacher does not have a chemistry background they should go to a colleague in the department to go through the procedure with them.
· Science safety procedures from Grade 9
· Concept of metals and non-metals from Grade 9 Science
1.3.1 Student Activity: Students observe a demonstration of the synthesis of sulfur dioxide. They record the annotated diagram and their observations. They generate a word equation and, with reference to the periodic table, a symbol equation for the reaction.
Teacher Facilitation: The teacher reviews metals and non-metals and demonstrates the synthesis of sulfur dioxide in a fume hood. The teacher leads the class in the development of an annotated diagram to summarize the method and a word equation for the reaction. The teacher reviews the periodic table and names and formulae of compounds from Grade 9 and then develops a symbol equation. Emphasis is on the use of symbols as short-form representations of information.
1.3.2 Student Activity: Students review the instructions for a lab exercise in which they synthesize and test magnesium oxide. They set up the apparatus, create an annotated diagram of the method, and then check with the teacher before proceeding with the exercise. Following the model provided in Activity 1.3.1, students create a report which includes their annotated diagram, observations, word and symbol equations, and answers to discussion questions.
Teacher Facilitation: The teacher provides the instructions for the oxidation of magnesium:
· A measured mass of a metal (approximately 1.0 g of magnesium ribbon) is heated in a crucible with the lid slightly ajar (to allow entry of air).
· Students determine the mass of the oxide produced, comparing it with the original mass of the magnesium.
· The oxide produced is dissolved in water and the pH of the solution is determined.
The teacher reviews technique and safety requirements, especially since this is the first use of a Bunsen burner in this course. The teacher checks the student setups which gives an opportunity to individually stress safety procedures and requirements such as the wearing of goggles. The teacher provides focus questions for the discussion which highlight the higher mass of the magnesium oxide than magnesium as a way of introducing the concept of conservation of mass/addition reactions.
1.3.3 Student Activity: Students review the instructions for a lab exercise in which they synthesize and test carbon dioxide and then follow the model in Activity 1.3.2 including the diagram, apparatus check, and report.
Teacher Facilitation: The teacher provides instructions for the oxidation of carbon, a non-metal, using a deflagrating spoon, igniting it in a Bunsen burner, and then allowing it to burn in one gas jar with some water at the bottom so that the gaseous product can be dissolved in the water and tested for pH, and then in another gas jar with some calcium hydroxide at the bottom so that the gas can be verified as carbon dioxide. Since this activity is carried out using the same model as the previous activity it allows for students to use feedback from the first to improve their performance on the second.
1.3.4 Student Activity: Students participate in a wrap-up discussion on synthesis reactions and make summary notes. They also update all three sections of their chemical log.
Teacher Facilitation: The teacher leads the discussion, providing further examples of synthesis reactions and of the acids and bases produced from them. The teacher gives instructions for the third section of the chemical log, Chemical Reactions, in which they set up a T-chart with word equations on one side and symbol equations on the other.
|
Task |
Tool |
Category |
Learning Skill |
|
Lab work and set-up |
Checklist |
Knowledge |
Work habits |
|
Annotated method diagram, observations, equations |
Marking scheme |
Inquiry, Communication |
|
· Put diagrams on the board and key words to remind students of experimental procedures.
· Provide exceptional and ESL students with instructions for the experiments in brief, clear language supplemented with diagrams.
Percival, S. and R. Wilson. Chemistry a Human Venture, Laboratory Manual. Irwin Publishing, 1988. ISBN 0-7725-1725-8
Zinck, E.E., R.L. Whitman, and R.A. Nalepa. Chemistry Today 1, Laboratory Manual, 3rd ed. Prentice Hall Canada, 1989. ISBN 0-13-129321-4
Time: 150 minutes
Students are introduced to single displacement reactions as another method by which bases can be produced. They continue to practise writing equations.
Strand(s): Chemistry
Specific Expectations
CH1.02P - demonstrate an understanding of chemical reactions, including conservation of mass, and their representation through balanced chemical equations;
CH1.03P - describe, using their observations, the reactants and products of a variety of chemical reactions, including synthesis, decomposition, and displacement reactions;
CH1.08P - name and write the formulae for common ionic and molecular compounds;
CH2.01P - through investigations and applications of basic concepts select and use appropriate apparatus, and apply WHMIS safety procedures for the handling, storage, disposal, and recycling of laboratory materials;
CH2.09P - represent simple chemical reactions using word equations, balanced chemical equations, and, where appropriate, molecular models.
· Review safety precautions required.
· Prepare materials for the activity.
· As written, Activity 1.4 provides opportunities for the teacher to demonstrate proper technique, safety precautions, and recording methods before students undertake the laboratory exercise in 1.4.3. If time permits and the teacher judges the students to be ready, they could carry out the lab exercises in 1.4.2 themselves.
· Science safety procedures
· Grade 9 Chemistry concepts: elements, compounds, symbols, and formulae
· Writing chemical equations
1.4.1 Student Activity: Students observe a teacher demonstration or video of the reaction of sodium with water. They record observations and generate word and symbol equations for the reaction.
Teacher Facilitation: The teacher cuts a small sample of sodium and allows it to react with a beaker half full of water, using safety precautions including goggles and a shield. After students speculate on the gas produced, the reaction is repeated in a large test tube with the gas produced being tested with a flaming splint to demonstrate the test for hydrogen. The teacher helps students come up with the word and symbol equations.
1.4.2 Student Activity: Students observe a demonstration of iron in copper(II) chloride, and copper in silver nitrate. They formulate questions about their observations (such as “Has the mass increased?”), suggest answers to their questions, and propose ways of finding out.
Teacher Facilitation: The teacher sets up the demonstrations so that students can observe the reactions while working on the other activities. The teacher encourages questioning and assures students that they will discuss answers later. Working with student suggestions, the teacher puts an iron nail in a test tube containing a solution of copper (II) chloride. After putting a stopper in the test tube, the mass is taken. The next day the teacher takes the mass again, to verify that there has been no change in mass despite the obvious reaction. Equations are developed. The teacher compares this reaction (without mass increase) to the mass increase observed when the students produced magnesium oxide.
1.4.3 Student Activity: Students carry out a lab exercise in which they react calcium with water and test the gas produced with a burning splint and the liquid with litmus paper. They create an annotated diagram to communicate the method used, record their observations, and write the word and symbol equations for the reaction.
Teacher Facilitation: The teacher provides the instructions for the exercise and reviews the safety precautions, including taking care to hold the calcium pieces only with tweezers, not directly with the hands. Calcium reacts very well with cold water so that the hydrogen gas produced can be collected by the downward displacement of water in four test tubes each filled with water. A different amount of hydrogen gas collected in each one. Two test tubes should be full of hydrogen gas: one should face mouth upwards while the other faces mouth downwards to show that hydrogen is less dense than air and escapes from the full test tube mouth upwards. The other two test tubes should be half full and one-quarter full of hydrogen gas. The gases are tested with a burning splint. Students determine the loudest of the popping sounds produced upon reaction with the flaming splint. For a quiz, students could be given a set of observations for the reaction of potassium with water and asked to generate the word and symbol equations, or they could be given the equation for a reaction between lithium and water and asked to predict the observations.
1.4.4 Student Activity: Students make a summary note and then update their chemical log.
Teacher Facilitation: The teacher provides summary notes on single displacement reactions, providing other examples and questioning students about the reactions they observed in Activity 1.4.2. The teacher reminds them to update all three sections of their log.
|
Task |
Tool |
Category |
Learning Skill |
|
Safety performance |
Checklist |
Inquiry |
Work habits |
|
Diagrams, observations, and equations |
Marking scheme |
Communications |
|
|
Quiz |
Marking scheme |
Inquiry |
|
· Provide partially completed equations and have students fill in the missing names.
· As an extension have students repeat the experiment with metals such as magnesium or zinc and hydrochloric acid.
· Provide a blank observation sheet prepared so that students need only fill in the blanks and can focus on what the teacher is doing in the demonstration.
Percival, S. and R. Wilson. Chemistry a Human Venture, Laboratory Manual. Irwin Publishing, 1988. ISBN 0-7725-1725-8
Laser disc – Chemistry at work: Image database for chemistry. Seattle: McGraw-Hill Inc., 1994.
Time: 150 minutes
Students investigate simple acid-base reactions as an example of double displacement reactions. They use different concentrations of acids and bases and determine the properties of the end products. This activity is very important in giving students the necessary background information and skills that they need for the end-of-unit task. It also ties into the acid rain section of the final unit.
Strand(s): Chemistry
Specific Expectations
CH1.06P - demonstrate an understanding of neutralization through investigation of simple acid-base reactions;
CH2.01P - through investigations and applications of basic concepts select and use appropriate apparatus, and apply WHMIS safety procedures for the handling, storage, disposal, and recycling of laboratory materials;
CH2.02P - through investigations and applications of basic concepts formulate scientific questions about acid-base neutralization reactions and outline experimental procedures to answer the questions;
CH2.03P - through investigations and applications of basic concepts demonstrate the skills required to plan and conduct practical experiments on acid-base neutralization reactions, and collect data using appropriate instruments and techniques in a safe and accurate manner.
· Review safety precautions necessary for work with acids and bases.
· Prepare the materials and solutions required. The acid and base used for the demonstration should be carefully prepared so that the concentration is accurate.
· Review references on microscale chemistry techniques and consider use of plastic, graduated droppers.
· If the students are ready (i.e., have demonstrated the necessary skills and sufficient regard for safety), they could carry out the procedure in Activity 1.5.1.
· Knowledge of solutions and methods of separating them from Grade 7
· Concept of concentration from Grade 7
1.5.1 Student Activity: Students observe the teacher demonstration of neutralization and participate in the discussion. Students suggest the use of litmus paper to indicate when the neutralization has taken place, and then observe the use of phenolphthalein as an endpoint indicator, turning from pink to clear.
Teacher Facilitation: The teacher reminds students about the end-of-unit task and about their initial investigation of antacids. The teacher then adds 10 mL of 0.1 M HCl to10 mL of 0.1 M NaOH, and asks how they would know if a chemical reaction had taken place. The teacher then tests the remaining solution with litmus paper as one form of evidence for a reaction, and evaporates the solution to show the salt that was produced. The teacher introduces the concept of double displacement reactions (changing partners) and develops the word and symbol equation for the reaction. The teacher asks what would have happened if different amounts of acid and base, or different concentrations, had been used. The teacher presents the challenge “How can you tell when neutralization has taken place?”, and follows the discussion with a demonstration of a neutralization using a burette of acid, an Erlenmeyer flask of base, and phenolphthalein as the endpoint indicator.
1.5.2 Student Activity: In pairs, students carry out the neutralization of a small amount (10 or 20 drops) of a base with the dropwise addition of an acid of unknown concentration, and determine whether the acid is a weak, medium, or strong concentration (i.e., has low, medium, or high concentrations of H+ ions). They record their method, including the number of trials used, their observations, their conclusions, and a word and symbol equation for the neutralization reaction they investigated. They share their results with the class and make conclusions regarding neutralization reactions and the salts produced. For a homework assignment they check out the ingredients on a bag of salt and vinegar chips to see if they can identify the chemical that is used to give the salt and vinegar flavour.
Teacher Facilitation: The teacher presents the challenge of determining concentration using a neutralization reaction and provides direction for the lab exercise. The teacher assigns each pair a different combination of 0.1 M base [NaOH or Ca(OH)2] and acid [HCl or CH3COOH] at one of three concentrations (0.01M, 0.1M, 1.0M). The teacher assists students with the lab exercise, indicating they may take several trials before they don’t overshoot the endpoint and emphasizing that they should get two trials that give roughly equal results. The discussion should include reference to neutralization occurring regardless of the type of acid or base or their concentration. Comparing the amounts used for neutralization of the same concentration of calcium hydroxide and sodium hydroxide with an equal concentration of acid could lead to a discussion of the number of hydroxyl ions from one molecule that end up in solution. This is a good time to introduce the need to balance equations based on the findings in the previous activity regarding conservation of mass.
1.5.3 Student Activity: Students update all three sections of their chemical log and work at balancing the equations in their Chemical Equations section.
Teacher Facilitation: The teacher reminds students about their log. The teacher works through some examples of balancing their equations and then encourages students to work individually or in pairs to balance their equations. The emphasis is on understanding that equations need to be balanced, not on having students master the balancing of equations. This would be a good time to check their logs and provide feedback.
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Task |
Tool |
Achievement Chart Categories |
Learning Skills |
|
Lab report |
Rubric |
Knowledge, Communication |
Teamwork |
|
Chemical log |
Checklist |
Knowledge, Communication |
Work habits, works independently |
· Confer with ESL and exceptional students to see that they understand and are using the PHAMOD format to write lab reports.
· Encourage exceptional and ESL students to use the computer to produce lab reports; with the assistance of a resource teacher students can create a “lab template” which they save and use each time a report is required.
Candido, J.L., et al. Heath Science Connections 10. D.C. Heath Canada Ltd., 1988. ISBN 0-669-95285-0
Slater, Alan and G.
Rapier-Canham. Microscale Chemistry Lab Manual. Addison-Wesley, 1994.
ISBN 0-201-60216-4, (Teachers’ Guide) ISBN 0-201-60215-6
Zinck, E.E., R.L. Whitman, and R.A. Nalepa. Chemistry Today 1, Laboratory Manual, 3rd ed. Prentice Hall Canada, 1989. ISBN 0-13-129321-4
Time: 150 minutes
Students design and make a soap product, using a base and oil, and then produce an advertisement for it.
Strand(s): Chemistry
Specific Expectations
CH2.03P - through investigations and applications of basic concepts demonstrate the skills required to plan and conduct practical experiments on acid-base neutralization reactions, and collect data using appropriate instruments and techniques in a safe and accurate manner;
CH2.05P - through investigations and applications of basic concepts analyse the data and information gathered to clarify aspects of the questions chosen;
CH2.06P - through investigations and applications of basic concepts communicate the results of the investigation, using a variety of oral, written, and graphic formats;
CH3.02P - investigate applications of acid-base reactions in common products and processes.
· This is a good point in the unit to have students continue work on their career assignment from Activity 1.1.4 and to have a guest speaker in.
· Prepare 6M NaOH solution (extreme caution needed!).
· Obtain oil. (Cottonseed oil is the best to use. Other oils such as castor oil, olive oil, or Crisco can be substituted. This will not work with mineral oil.)
· Prepare other materials required.
· Ethanol is also required. Caution: extremely flammable. Make sure that there are no open flames where the soap is being prepared. It is best to use hot plates instead of burners for this lab.
· Consider assigning students a homework investigation several days before this exercise in which they look at a variety of soaps that are available in stores to get ideas for a soap design and any added ingredients. Have them check out bulk food stores, health food stores, or cosmetics counters of drug stores.
· As an alternative to this activity, if using 6.0 M NaOH is a concern with your class, consider reviewing the soap-making process, or demonstrating it, and then having students design and carry out a consumer product test to compare two or more soaps of their choosing.
· Lab safety procedures
1.6.1 Student Activity: Students review the instructions for soap-making, identify the safety hazards, and determine the precautions that should be taken. They then choose which oil to use for their soap and determine whether they want to add colour or scent or some other material, such as oatmeal. They may also choose to form it into a shape or make a liquid soap by mixing with water once the soap itself is made. They obtain teacher approval and then prepare their soap.
Teacher Facilitation: The teacher introduces soap-making as a common process which is an example of an acid-base reaction. The base (which in pioneer times was lye, produced by leaching water through wood ashes) splits the fat or oil (in pioneer times they used animal fat) into its component parts of fatty acids and glycerol, and then forms a salt with the fatty acid, which is generally a solid at room temperature. Ethanol is used to help the base and the fat mix. The teacher provides the instructions for soap-making:
· Measure 10mL of oil into a 125 mL beaker and add 10 mL of ethanol and 10 mL of 6M NaOH to the beaker.
· Heat the mixture in a hot-water bath on a hot plate, constantly stirring with a glass rod until it becomes thick and a waxy solid forms.
· Add 20 mL hot distilled water and 30 mL saturated sodium chloride solution. Stir the mixture, breaking up lumps with the stirring rod.
· Add any colour, scent, or other ingredients at this time and mix well.
· Let stand for two minutes.
· Scoop the curds of soap in the upper layers of the water onto a paper towel.
· Squeeze out as much liquid as possible, and form into shape or use to make liquid soap.
The teacher completes a safety checklist for each lab group and supervises the process.
1.6.2 Student Activity: Students test their product by adding a small amount to water in a test tube, shaking to see how much lather forms. They also test the pH of the solution. They then create an advertisement for their product.
Teacher Facilitation: The teacher provides direction on the testing, emphasizing safety precautions as the soap may still be quite basic.
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Task |
Tool |
Category |
Learning Skill |
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Safety precautions |
Checklist |
Knowledge |
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Advertisement |
Rubric |
Inquiry, Communication, Making Connections |
|
· Organize heterogeneous groups of students to accommodate student strengths and weaknesses.
· As an extension have students test the lathering ability of their soap and compare it to commercial products.
Candido, J.L., et al. Heath Science Connections 10. D.C. Heath Canada Ltd., 1988. ISBN 0-669-95285-0
Percival, S. and R. Wilson. Chemistry,
a Human Venture. Toronto: Irwin Publishing, 1988.
ISBN 0-7725-1696-0
Zinck, E.E., R.L. Whitman, and R.A. Nalepa. Chemistry Today 1, Laboratory Manual, 3rd ed. Prentice Hall Canada, 1989. ISBN 0-13-129321-4
Time: 100 minutes
This activity furthers the study of chemical reactions by introducing students to complete and incomplete combustion. Students produce acetylene gas and ignite different air-acetylene mixtures. The follow-up to the laboratory activity includes examination of problems associated with combustion products -- carbon dioxide as a greenhouse gas, carbon monoxide poisoning, etc. Information presented in this activity is revisited in Making Connections (Unit 5).
Strand(s): Chemistry
Specific Expectations
CH1.02P - demonstrate an understanding of chemical reactions, including conservation of mass, and their representation through balanced chemical equations;
CH1.03P - describe, using their observations, the reactants and products of a variety of chemical reactions, including synthesis, decomposition, and displacement reactions;
CH1.08P - name and write the formulae for common ionic and molecular compounds;
CH2.08P – conduct experiments to determine the factors that affect the rate of a chemical reaction;
CH2.09P- represent simple chemical reactions using word equations, balanced chemical equations, and, where appropriate, molecular models;
CH3.03P- relate chemical reactions to familiar processes encountered in everyday life and identify careers that require knowledge of such processes;
· Review the safety procedures required for this activity. The teacher must take time to prepare students properly by reviewing all appropriate safety rules.
· Calcium carbide should not be touched; a scoopula should be used.
· The teacher should be responsible for providing the pieces of calcium carbide.
· All acetylene generators should be cleaned up before air-acetylene mixtures are ignited.
· Students must wear goggles at all times.
· Consider doing this as a demonstration if you are concerned with the safety of your class doing this exercise.
· Students were introduced to combustion reactions in Grade 9.
1.7.1 Student Activity: Students work in pairs to produce and collect acetylene gas by reacting a small piece of calcium carbide with water. Four test tubes are filled with water and inverted in a 600 mL beaker half-filled with water. The piece of calcium carbide is added to the water in the beaker and acetylene is collected by the downward displacement of water. One test tube is entirely filled with acetylene; a second, two-thirds filled; a third, one-third filled; and the last, one-tenth filled. The test tubes are pulled out of the water and stoppered immediately. Prior to igniting the test tubes, students predict which test tube produces the best combustion. Students record and explain their observations, including reference to why the combustion reaction occurred at different rates.
Teacher Facilitation: The teacher begins the activity with a directed lesson that builds on the students’ knowledge of combustion from Grade 9 and previous activities in Grade 10 and introduces the concept of complete and incomplete combustion. Discussion of the properties of the combustion products can take place at this point or be left to after the laboratory exercise. The teacher explains the role of carbon dioxide as a greenhouse gas and carbon monoxide poisoning. The relationship between products of combustion and acid rain can be discussed as well. Students are familiar with some of these concepts and should be able to add to the discussion. During the laboratory activity the teacher should monitor the calcium carbide and ensure that acetylene generators are shut down before igniting the gas mixtures in the test tubes. Prior to igniting the gases, have students predict the nature of each reaction. Most students expect the test tube filled with acetylene to be the most reactive. Possible applications include the use of acetylene in cutting torches and welding where a tank of oxygen is used along with the tank of acetylene to produce a very hot flame. Antique lamps for cars and bicycles as well as miner’s lamps were constructed so that water would drip on calcium carbide and the resulting acetylene ignited.
1.7.2 Student Activity: Students write word and symbol equations for the three cases involved. Students then update their chemical log.
Teacher Facilitation: The teacher assists students in developing the equations and reminds them to update their log.
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Task |
Tool |
Category |
Learning Skill |
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Observation charts and conclusions |
Rubric |
Knowledge, Inquiry, Communication |
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|
Lab work |
Checklist |
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Work habits |
· Provide partially completed equations.
Percival, S. and R. Wilson. Chemistry a Human Venture, Laboratory Manual. Irwin Publishing, 1988. ISBN 0-7725-1725-8
Time: 150 minutes
This activity allows students to examine factors that affect reaction rates and to complete a design challenge in which they use a chemical reaction to pop the lid off a plastic film container. This experiment helps students to understand the importance of changing only one variable at a time. This is a practical example of an acid base reaction that ties in with the end-of-unit task.
Strand(s): Chemistry
Specific Expectations
CH1.04P - describe qualitatively, using their observations, how factors such as heat, concentration, light, and surface area can affect rates of chemical reactions;
CH2.08P - conduct experiments to determine the factors that affect the rate of a chemical reaction;
CH3.02P - investigate applications of acid-base reactions in common products and processes.
· Activity 1.8.1 is written as demonstration/Socratic lesson to save time. However, if time permits and student lab skills are in place, this activity could be restructured and carried out by students.
· Students must wear safety goggles during this experiment.
· Assign a specific time for each student group. These times may vary from group to group.
· To cut down on the mess, it would be advisable to have students carry out this activity in a large plastic tub or a large clear plastic bag.
· Consider having students practise with baking soda and vinegar, then perform the activity using seltzer tablets (or baking powder) and water.
· Contact local pharmacies or drug companies to inquire about supplies of expired tablets to reduce costs.
· Collect plastic film canisters prior to the activity.
· Some students may need assistance in designing data tables.
· Additional variables such as surface area and temperature could be investigated as an extension.
· Experience in controlling variables
· Experience in experimental design
· Use of balance and graduated cylinder
· Experience in data presentation
1.8.1 Student Activity: Students participate in an introductory discussion about reaction rates, including everyday examples where the rates of chemical reactions are modified. Students record observations as the teacher performs comparative demonstrations of factors that affect reaction rates, using the reaction between calcium carbonate and HCl. As the demonstrations proceed, students identify the factors that influence the rate of a reaction: concentration of solution, surface area of solid, and temperature of reaction.
Teacher Facilitation: The teacher introduces the topic by noting the variety of chemical reactions they have studied, with reference to the Chemical Equation section of their chemical log, asking how fast each of them happened. The teacher then demonstrates, the reaction between CaCO3 and HCl at different temperatures, acid concentrations and surface areas of the solid. Students are questioned to get them to identify the factors affecting the rate of this particular reaction and how the rate is measured.
1.8.2 Student Activity: Students observe demonstrations and participate in discussion. They then work in pairs to design and safely perform the activity in which they pop the lid from a plastic film canister, in a specified amount of time, using a seltzer tablet. The amount of time can be different for each group or the same. They manipulate the amount and condition of each material to produce the reaction in the time required. They record each attempt in an appropriate data table.
Teacher Facilitation: As an introduction, the teacher demonstrates the reaction between baking soda and vinegar, developing the equation for the reaction. This reaction is used in baking, where the bubbles produced by the reaction between baking soda and acid in the recipe (fruit juice, vinegar, sour cream, or yogurt) are trapped in the dough or batter and expand in the heat of the oven, making the batter rise. The teacher then demonstrates the reaction between baking powder and water and develops the equations, explaining that in this case the acid is in a powder form and is not active until it dissolves in water; it reacts further when heated. The teacher lists the ingredients in baking powder and asks students which ingredient is the acid. The teacher then explains that a similar type of reaction occurs in seltzer tablets, and challenges students to use a tablet’s reaction with water to pop the lid of a film canister in a specified length of time. The teacher assigns an appropriate time for the chemical reaction to each group. This can be similar or different for each group. The teacher ensures that safe lab procedures are followed at all times. The teacher monitors the collection and recording of data.
1.8.3 Student Activity: Students update their chemical log. In preparation for the next activity, they review the compounds they have listed and look for patterns in the names and symbols.
Teacher Facilitation: The teacher reminds students to update their log and adds to the classroom list as well.
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Task |
Tool |
Category |
Learning Skill |
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Method design |
Rubric |
Inquiry |
Initiative |
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Performance assessment |
Time check |
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· Arrange heterogeneous groupings of students.
· Provide exceptional and ESL students with a printed list of chemical compounds and formulae.
Crucible, Volume 31: Number 1, September 1999. Science Teachers Association of Ontario.
Time: 100 minutes
Students consolidate their understanding of the relationships among chemical formulae, composition, and names by playing a game similar to bingo.
Strand(s): Chemistry
Specific Expectations
CH1.01P - recognize the relationships among chemical formulae, composition, and names;
CH1.08P - name and write the formulae for common ionic and molecular compounds;
CH3.01P - use scientific nomenclature to identify common consumer products.
· Bingo cards are prepared using a variety of formulas that have been used in the previous lab activities.
· Similar family names can be included as well for more of a challenge.
· Collect prizes for the game.
· If students do not know symbols for elements very well, it would be worthwhile spending time playing “Elements chemo” which is similar to the compound game but has single element names on the card instead of combinations.
· Teacher should be familiar with how to run a bingo game and should call out the first game and then have a student volunteer call out the next game. The responsibility can rotate from one student to another.
· Rules of the game are announced before the start of the game (what constitutes a win?): runs up and down, runs across, four corners filled, or, for more of a challenge, a full card.
· A list of compound names is prepared so that they can be called out without repetitions occurring and so that the teacher or student have a check of the names that should be called back by the winning student(s).
· Students must be familiar with the symbols for the elements that they learned in Grade 9
1.9.1 Student Activity: Students participate in the class discussion on the naming of compounds and identify the patterns in their list of compounds.
Teacher Facilitation: The teacher reviews the periodic table and the concept of metals and non-metals. The teacher asks students to highlight the compounds in their list that start with a metal name and notes that the element name is used as the first part of the name. The teacher asks students to underline any of the highlighted names which end in “ide” and to locate on the periodic table the corresponding element, asking whether it is a metal or non-metal. The teacher asks students to look at those highlighted names which have another ending, to identify the ending, and then to investigate the symbol to see how they are different from the other compounds. The teacher summarizes the rules for naming simple ionic compounds and explains that there are also rules for naming molecular compounds. This activity could be done as a written assignment, individually or in small groups, instead of as a class discussion.
1.9.2 Student Activity: From the list of names and formulae on the board student fill in the formulae on a blank CHEMO sheet. Students pick up a gameboard for “Compounds chemo” and prepare small pieces of paper to use as chips to cover the compound names as they are called out. Students yell out “chemo” if they have corners filled or cross runs or runs up or down on the card. They must then call back the compounds that they have covered on their card in order to receive their prize.
Teacher Facilitation: The teacher uses the classroom list for the generation of the CHEMO sheets. The teacher or a student volunteer calls out the names of the formulas from the board using a different letter of CHEMO for each formula. The teacher or student must record the formulas in order to check the student who yells out “CHEMO” when they have completed a run.
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Task |
Tool |
Category |
Learning Skill |
|
Quiz |
Marking scheme |
Knowledge |
|
· Provide extra time for the quiz or allow students to write in the resource room.
Time: 200 minutes
This end-of-unit task allows students to design their own procedure to determine which antacid is the best in terms of cost and neutralization capacity. They have already been introduced to the concept of neutralization and now use it in a practical comparison of commercial antacids. If they have worked through all the preceding activities they should have the skills and knowledge needed to do this analysis effectively.
Strand(s): Chemistry
Specific Expectations
CH1.06P - demonstrate an understanding of neutralization through investigation of simple acid-base reactions;
CH2.01P - through investigations and applications of basic concepts select and use appropriate apparatus, and apply WHMIS safety procedures for the handling, storage, disposal, and recycling of laboratory materials;
CH2.02P - through investigations and applications of basic concepts formulate scientific questions about acid-base neutralization reactions and outline experimental procedures to answer the questions;
CH2.03P - through investigations and applications of basic concepts demonstrate the stills required to plan and conduct practical experiments on acid-base neutralization reactions, and collect data using appropriate instruments and techniques in a safe an accurate manner;
CH2.05P - through investigations and applications of basic concepts analyse the data and information gathered to clarify aspects of the questions chosen;
CH2.06P - through investigations and applications of basic concepts communicate the results of the investigation, using a variety of oral, written, and graphic formats;
CH3.01P - use scientific nomenclature to identify common consumer products;
CH3.02P - investigate applications of acid-base reactions in common products and processes.
· Collect a variety of commercial antacids for student use in the lab.
· The cost of the antacids should be visible on the containers they are stored in for a cost analysis.
· Teacher could go to drugstores and ask the pharmacist if they have any antacids that have gone past their expiry date that could be purchased at a reduced price or given gratis for school use.
· Students could bring in their own antacids and test the ones they are interested in.
· Students should be encouraged to compare their results as they work through the activity.
· Some students may need help in doing the mathematics required for a cost analysis. The teacher may have to spend time going over how to do these calculations.
· Collect examples of consumer reports or product analyses to use as examples for students.
· Concepts developed through this unit
1.10.1 Student Activity: Students, in pairs, identify the chemical ingredients in the three different kinds of antacids from the labels and then make up their own procedure to analyse the antacids with respect to their effectiveness. The antacid that neutralizes the most acid for the lowest price is called the “best buy”. If the student is using a tablet form of the antacid they must crush it well in a mortar and pestle, add water to the mortar, and pour the contents into an Erlenmeyer flask. They obtain approval for their method and carry it out.
Teacher Facilitation: The teacher reviews the task and leads a discussion on possible approaches to use in their procedure. Students realize that what they are doing is the reverse of the neutralization that they did in the earlier activity. In order to compare class results it would be advisable to use the same quantities of antacid to be tested. It would also be advisable to use only one form of antacid, either liquid or solid, so that other variables are not introduced into the experiment. Congo red (0.1%) should be used as the indicator. A 10% HCl solution should be added to the antacid and the number of mL used recorded.
1.10.2 Student Activity: Students use their group data to write a consumer report on the antacids investigated, including a summary of the method they used, with diagrams, their results, and their conclusion.
Teacher Facilitation: The teacher reviews the requirements for the report.
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Task |
Tool |
Category |
Learning Skill |
|
Consumer report |
Rubric |
Knowledge, Inquiry, Communication, Making Connections |
Organization |
· Provide extra support to students with the calculations for the cost-analysis.
· Have students keep a daily log of what they accomplished and what they need to do next, or provide step-by-step instructions.