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Three day lesson
plan: Science 10
Unit “A”:
Energy & Matter
in Chemical
Change.
EDPS 364
A comprehensive three day lesson plan for
teaching concepts regarding energy and matter in
chemical change
University of Alberta
Megan Malone
Rebecca Redding
Daniel Brady
Orysia Stefiuk
Matthew Balfour
Karl Hoehne
10/27/2008
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General Learner Outcome (GLO)
 Identify and classify chemical changes, and write word and balanced chemical
equations for significant chemical reactions, as applications of Lavoisier’s law of
conservation of mass
Specific Learner Outcomes (SLO)
Outcomes for Science, Technology and Society (STS) and Knowledge
 Define the mole as the amount of an element containing 6.02 × 10 23 atoms
(Avogadro’s number) and apply the concept to calculate quantities of substances
made of other chemical species (e.g., determine the quantity of water that
contains 6.02 × 1023 molecules of H2O) [Will be assessed in the assigned
questions from day one and lab report on day three]
 Interpret balanced chemical equations in terms of moles of chemical species,
and relate the mole concept to the law of conservation of mass [Will be assessed
in the assigned questions from day one and lab report on day three]
Skill Outcomes
 Initiating and Planning
o state a prediction and a hypothesis based on available evidence and
background information (e.g., state a hypothesis about what happens to
baking soda during baking) [Will be assessed in the lab write up on day
two]
 Performing and Recording
o carry out procedures, controlling the major variables and adapting or
extending procedures (e.g., when performing an experiment to illustrate
conservation of mass, demonstrate an understanding of closed and open
systems and control for loss or gain of matter during a chemical change)
[Will be assessed in lab procedure on day three]
o demonstrate a knowledge of WHMIS standards by selecting and applying
proper techniques for the handling and disposal of laboratory materials
(e.g., recognize and use Material Safety Data Sheets [MSDS] information)
[Will be assessed in lab report on day three]
o select and use apparatus, technology and materials safely (e.g., use
equipment, such as Bunsen burners, electronic balances, laboratory
glassware, electronic probes and calculators correctly and safely) [Will be
assessed in lab report on day three]
 Analyzing and Interpreting
o compare theoretical and empirical values and account for discrepancies
(e.g., measure the mass of a chemical reaction system before and after a
change, and account for any discrepancies) [Will be assessed in the lab
write up on day two]
o identify and explain sources of error and uncertainty in measurement,
and express results in a form that acknowledges the degree of
October 27, 2008
Unit A – Energy and Matter in Chemical Change
uncertainty (e.g., measure and record the mass of a material, use
significant digits appropriately) [Will be assessed in lab report on day
three]
 Communication and Teamwork
o communicate questions, ideas and intentions; and receive, interpret,
understand, support and respond to the ideas of others (e.g., use
appropriate communication technology to elicit feedback from
others)[Will be informally assessed during STSE discussion]
o select and use appropriate numeric, symbolic, graphical and linguistic
modes of representation to communicate ideas, plans and results (e.g.,
use appropriate scientific [SI] notation and IUPAC nomenclature)[Will be
assessed in lab report/write up from day one and day two]
Attitude Outcomes
 Interest in Science
o Show interest in science-related questions and issues, and confidently
pursue personal interests and career possibilities within science-related
fields (e.g., apply concepts learned in the classroom to the everyday use
of chemicals; show interest in a broad scope of chemistry-related careers)
[Will be informally assessed during STSE discussion]
 Scientific Inquiry
o Seek and apply evidence when evaluating alternative approaches to
investigations, problems and issues (e.g., evaluate inferences and
conclusions based on particles of matter that cannot be observed directly)
[Will be assessed in discussion of ice-bag demo and lab report on day
three]
 Collaboration
o Work collaboratively in planning and carrying out investigations, as well
as in generating and evaluating ideas (e.g., contribute to group work
willingly, assume a variety of roles and accept responsibility for any
problems that arise) [Will be assessed in lab report on day three]
 Stewardship
o Demonstrate sensitivity and responsibility in pursuing a balance between
the needs of humans and a sustainable environment (e.g., recognize that
environmental consequences may arise from the development, use and
disposal of chemical materials) [Will be informally assessed during STSE
discussion]
 Safety
o Show concern for safety in planning, carrying out and reviewing activities
(e.g., acknowledge the need for regulations to govern the storage,
handling and disposal of potentially hazardous materials in the school
laboratory and at home or in the workplace) [Will be informally assessed
during lab and formally in lab report on day three]
October 27, 2008
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
Objectives of Lesson (Communicated to Students)
 Each student will be able to define what a mole is. They should be able to apply
this concept to calculate quantities of substances made from chemical
compounds.
 Each student will be able to write, balance and interpret chemical equations in
terms of moles of a chemical species and relate this to the concept of the law of
conservation of mass.

Anticipatory Set (Hook)
 DEMO: Bag of Ice Demo - The Conservation Of Mass
Source: Jake Carter, Douglass Math and Science Academy, 543 North Waller
Chicago IL
 Objective: Addresses the misconceptions that melted water is heavier than
frozen ice and that fact that “denser” does not mean “heavier”. Also addresses
the misconception that a change in phase results in a change in mass.
Pre-Requisite Knowledge
 Students should have some understanding of the atomic theory and
conservation of mass from the grade 9 curriculum.
 What is the atomic theory? (whole class discussion)
 What happens in a chemical reaction? Phase change?
Procedure (40 minutes)
 State the activity of the day – Teaching the concept of Energy and Matter
 Inform students of learner outcomes and expectations
 General Questioning
o What is matter?
o What is mass?
o Does all matter have mass?
 Is all matter made of atoms? Does the spacing of atoms effect
mass?
 Demonstrate ice activity:
o Split class into discussion groups, post the following questions:
 What is the composition of ice? Water?
 Will there be a change in mass when the ice melts?
 Which weighs more, water or ice?
o Ask for written predictions and explanations to those questions
o Record predictions (on board)
 Aside: Move away from demo to let ice melt and begin to
introduce the law of conservation of mass


October 27, 2008
Day One
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

Law of conservation of mass – during a reaction, the total mass of
the reacting substances (reactants) is always equal to the total
mass of the resulting substances (products).
 Lavoisier discovered this principle while carrying out
reactions in closed systems, noticing that the system did
not gain or lose mass. In a lab setting, we don’t always
have a closed system, and therefore the mass of gas is lost,
so measurements are contrary to this principle.
 Open system – a system that exchanges matter and energy with
it’s surroundings
 Closed system – a system that does not exchange matter with it’s
surroundings
 Isolated system – a system that does not exchange matter or
energy with it’s surrounding
o Ask students if they would like to review their predictions regarding the
weight of the bag
o Weight the bag (demonstration concluded)
 Does anyone have any questions regarding the constant weight of
the ice-water bag?
 If students do have further questions regarding the theory of
conservation of mass address these now, or make note of it so
you can get examples for the next class.
 What does this mean for evaporation? Will there be a change in
mass in an evaporation phase change? Keep this question in mind
for tomorrow’s lab.
Introduction into balancing equations based on the principle
o The law of conservation of mass demands that the mass and molarity of
the reactants be equal to the mass and molarity of the products
o Example of : H2 + O2  H2O on board
o Exercises of various “skeleton” equations that they solve as a group (10
minutes)
Introduce the concept of Avogadro’s number/molar mass of elements and
compounds
o Avogadro’s number – one mol of a compound contains 6.022 141 99 x
1023 atoms of the given compound
o Molar mass of an single element
 Molar mass- refers to the mass of 1 mol of any pure substance
(units = g/mol)
 Ex. Fe has a molar mass on the periodic table of 55.85g/mol.
 If an element exists as a compound ex. N2 the molar mass of that
compound is multiplied by the number of atoms.
o Molar mass of compounds
 Ex. CO2 = (1 x 12.01) + (2 x 16) = 44.01 g/mol
October 27, 2008

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


Students need to take into account multiple elements in a
compound and individual weights of those compounds.
Introduce the concept of conversion between mass and moles
o Equation – n = m/M
 n = amount (mol)
 m = mass (grams)
 M = molar mass (grams/mol)
o Molar mass of compounds/elements can be used, when given grams or
moles, to convert to either grams or moles depending on the units given
 Ex. Convert 3 grams of O2 to mole
 O2 = 32g/mol
 n = 3grams O2 / 32 (grams/mol) O2 = .094 mol
The mole and the law of conservation of mass
o students will use mole concept to relate coefficients in balanced chemical
equations to the mass of the substances involved
Balanced Chemical
Equation
Illustration
2H2 (g) + O2(g)  2H2O(l)
Amount (mol):
Mass (g):
Total mass (g):
2 mol H2 + 1 mol O2  2 mol H2O
4.04 g H2 + 32 g O2  36.04 g H2O
36.04 g reactants
 36.04 g products

Activity: Marshmallow Equations
o Have students get into groups of 4 or 5 and give each group a set of
marshmallows and toothpicks. Each group will be responsible for
using the marshmallows and toothpicks to visually represent an
equation and balance it. Move amongst the groups to ensure they
are representing them correctly. 5-7 minutes into the activity,
provide students with the correctly balanced equations so they are
able to catch any mistakes they are making. Allow students 5 more
minutes to complete activity. Allow them to eat the marshmallows
when they’re finished
o Equations:
 Al + O2  Al2O3 (4Al + 3O2  2Al2O3)
 H2 + O2  H2O (2H2 + O2  2H2O)
 Fe + O2  Fe2O3 (4Fe + 3O2  2Fe2O3)
 K + Br2  KBr (2K + Br2  2KBr)
 Mg + P4  Mg3P2 (6Mg + P4  2Mg3P2)
 Cu + O2  Cu2O (4Cu + O2  2Cu2O)
 Fe + Cl2  FeCl3 (2Fe + 3Cl2  2FeCl3)
October 27, 2008
TABLE 3.5 - drawn on board and explain
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
Closure (20 minutes)
 Review and summarize the main points (Law of conservation of mass,
open/close/isolated systems, balancing equations, molar mass of
elements/compounds, conversion between mass and mol, and the mol and the
law of conservation of mass)
o Ask various questions of examples of reactions where it would be hard to
measure the mass of the products
o Ask questions for examples of open/closed/isolated systems
Evaluation (20 minutes)
 Observe steering group for student reactions (head nods, eye contact etc…
indicates understanding).
 Ask probing questions during the lesson.
 Group work: Balancing equations (check work and observe groups).
 Individual seatwork: (See attached)
October 27, 2008

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
Key Concepts
 The student will be able to communicate their results of the experiment in a
written lab report, using a standard lab reporting form. They will be able to
articulate the experiment in our post lab discussions.
 Students will create a scientific graph showing results of the experiment.
 Students will be able to draw conclusions about the conservation of matter
based upon the experiment

Objectives of Lesson (Communicate to Students)
 By the end of today’s lab you will be able to understand and discuss the results
of your experiment. You will be able to explain in discussion or writing, how the
type of system affects the Law of Conservation of Mass.

Materials
 Teacher Materials
o Lab Coat
o Goggles
o Weight Scales (~10)
o Alka-Seltzer tablets (~1 bottle)
o Erlenmeyer Flasks (~30)
o Bag of Balloons
o Baking Soda
o Vinegar
o Paper Towel
o Test tubes
 Student Materials
o Lab Coat
o Goggles

Purpose of today’s lesson: To address the misconception students have concerning
changes in state and how this can affect the mass of a closed system. Students seem
to believe that if a substance converts to gas that somehow the system becomes
lighter (struggle to see how gas can have weight).

Pre-Requisite Knowledge
 Students should have knowledge of atomic theory, chemical nomenclature,
elements and compounds from the grade 9 curriculum
October 27, 2008
Day Two
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Procedure (50 minutes)
Introduction to lab - Providing necessary background information:

Alka-Seltzer tablets - This experiment will help students with their
understanding of matter in all of its phases. It will show that in a chemical
reaction where a gas is produced, the mass does not change. The mass does
not change provided none of the gas is allowed to escape. This will give
evidence for conservation of mass. In furthering their knowledge of the laws
of conservation of mass, the loss in mass can be accounted for, when the gas
is allowed to escape from the container which it is produced in. This will
prove that gas does have mass.

Set Up:
o Students will be asked to predict what the mass of the system will be
at each weigh-point (the same, greater, or less). They will be asked to
provide these predictions and their reasoning behind them in written
form, and include it with their analysis questions.
o Students are asked to work with their lab partner to carry out this
experiment. The Students will collect all materials from the teacher's
material lab station in the front of the room.
o Students will construct an apparatus including an Erlenmeyer flask
with 1/8 of an Alka-seltzer tablet in the bottom. The student will then
fill a small test tube with water and carefully place the small test tube
inside the flask being careful to no tip the test tube over.
o When the test tube is in place inside the flask, the student will then
attach a balloon to the top of the flask, weigh the apparatus, return
to their benches and then tip the flask so that the water in the test
tube mixes with the Alka-seltzer.
o The students will then allow the reaction to proceed. When the
reaction stops the student will then weigh the entire apparatus once
again, noting that the mass has not changed.
o The student will then remove the balloon from the apparatus and
weight the system again. The solution shows a small change in mass.
o Record the data on the data graph or chart.
This experiment shows students that the law of conservation of mass does hold
true for experiments that produce gas. The law can only be truly observed in a
closed system, and as soon as the system is opened mass appears to be less on
the reactants side than the products side.
October 27, 2008

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Questions for analysis (to be answered by the end of the lab, in written
form, one copy per group)
o Does the reaction cause a change in mass?
o Do gasses have mass? How do we know this?
o What gas is being produced by the reaction?

Closure (20 minutes)
 Observe during lab work. Interact with groups: Probing questions.
 Check lab write up and provide timely feedback.
o Understanding of Law of conservation of Mass
 Conversions (moles, mass, atoms…), amounts of reactants/products

Evaluation (10 minutes)
 Assigned individual seatwork questions
 Lab write up handed in at the end of class (to be checked for understanding,
not for marks)
October 27, 2008

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
Key Concepts
 Identify both products of reaction
 Write an equation (balanced)
 Calculate number of moles of gas that was produced.

Objectives of Lesson (Communicate to Students)
 By the end of today’s class you will be able to:
o Solve molarity questions using knowledge and understanding of mole
concept
o Independently perform a decomposition reaction
o Discuss results and analyze data

Materials
 Lab coat
 Safety glasses
 Erlenmeyer flasks (1 for each group)
 NaClO(s) (~2.000 grams per group)
 Bunsen Burner/Hot plate (~15)
 Scale (to the nearest hundredth)
 Clamps

Pre-Requisite Knowledge
 Students should have knowledge of chemical nomenclature, lab safety
procedures and WHMIS.
 Students will have seen a demo or performed an experiment on
decomposition reactions earlier in this unit when we went over the type of
reactions.

Procedure (40 minutes)
 Prelab: Review lesson 2 group questions from last day
 Guidelines for starting laboratory:
o In pairs weigh out approximately 2.00 grams (nearest hundredth) of
NaClO3(s). You will be performing a decomposition reaction using an
Erlenmeyer flask, clamps and Bunsen burner.
o Create your own step by step procedure for this experiment and include
it in your lab write up (using the template provided - attached).
o The product of this decomposition will be a white solid (identify), and
unknown gas (identify).
o Remember: Weigh product at the end.
October 27, 2008
Day Three
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Closure (20 minutes)
 STS – Recognize that environmental consequences may arise from the
development, use and disposal of chemical material.
 Class discussion in groups to answer the question: What do we need
to know before we can dispose of a chemical compound? What
disposal categories can you think of for different types of chemicals?
1. Potential answers:
2. Flammable – alcohols
3. Acids – hydrochloric acid
4. Bases – sodium hydroxide
5. Oxidizers - Halogens
6. Reactive with water - Arsenic
7. Mercury compounds - Mercury
8. Polychlorinated biphenols - PCB
9. Aerosols - asbestos
10. Oils – mineral oils, organic oils, food oils
 Go through the categories with the class and ask for examples of each
category. Go over the three types of disposal in the lab
 Organic – Chemical compounds based on carbon chains or rings and also




containing hydrogen, with or without oxygen, nitrogen, and other elements
Inorganic - compounds that are not carbon based such as salt, potassium,
vitamins, minerals
Heavy Metals - Metallic elements with high atomic weights, such as, mercury
chromium cadmium, arsenic, and lead. Even at low levels these metals can damage
living things. They do not break down or decompose and tend to build up in plants,
animals, and people causing health concerns
Ask class for examples of effects a waste would have on the environment if
not disposed of safely (in regards to water ecosystem, plant ecosystem). Link
these effects up the food chain to yourself.
 Groundwater contamination
 Mercury contamination in fish and water systems
 Destruction of plants and symbiotic partners
 Disinfection by-products in water treatment facilities
 Address misconceptions from day 1 and 2
 Probe to assess whether the thought process has been modified.
 Clarify any problems students are still having with concepts.
Evaluation (20 minutes)
 Completion of lab report is the evaluation for this exercise, including:
 % error in procedure
 Formulation of correct balanced equation
 Calculation of amount of gas lost to the atmosphere by reaction
October 27, 2008

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References
1. Textbook:
Gue, D., Hutton, G., Jeans, S.L., Leong, E., Lunn, D., Mason, A., McGuire, B., Painter, D.,
Searle, S., Siler, R., Webb, M. 2004. Science Focus 10: Science, Technology, Society.
McGraw-Hill Ryerson Ltd. Whitby, Ontario.
2. Curriculum:
Science 10 Program of Studies Alberta. 2005. Alberta Education. Edmonton, Alberta.
3. Additional Information for STSE issue:
Summit to the Sea: Disease Pollution. 2002.
http://coastgis.marsci.uga.edu/summit/k12chemwaste.htm
4. Information on student misconceptions:
Johnston, Kate and Scott, Philip. (1991). Diagnostic Teaching in the Science Classroom:
teaching/learning strategies to promote development in understanding about
conservation of mass on dissolving', Research in Science & Technological
Education,9:2,193 — 212
October 27, 2008
Pyke, C & Ochsendorf. R., (2004). The Conservation of Matter Assessment Manual, Scale
Up.
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Names: _______________
_______________
Experiment Template – Decomposition of Sodium Chlorate (NaClO3(s))
Weight of empty apparatus (g)
Initial weight of sample (g)
Final weight of system (g)
Final weight of sample (g)
(final weight of system – weight
of empty apparatus)
October 27, 2008
Procedure
 Outline the basic steps you will perform in this experiment
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Safety
 Outline any major precautions that must be taken during the course of the experiment
and Provide MSDS information, including the primary hazards and emergency
procedures.
Observations:
 Note any changes you see as the reaction progresses (can you see a gas being produced?
Color change? Does the appearance of the solid change? Etc.).
-
October 27, 2008
Reaction
 Write the balanced chemical equation, including the unknown products; include the
molar masses of each compound/element.
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Calculations
 Use stoichiometry to calculate the theoretical amount of both products produced in the
reaction.
Unknown 1: Solid – calculate amount in grams
Unknown 2: Gas – calculate amount in moles
Percent Error Calculations
 Calculate the % error value (theoretical – observed/theoretical) for the solid product and
provide two possible explanations for that value (only one can involve human error).
% error
October 27, 2008
Explanations for percent error (provide 2):
P a g e | 17
Extra info for Environmental issue
http://coastgis.marsci.uga.edu/summit/k12chemwaste.htm
Industries are built next to rivers so that wastes can be flushed right into the river. Waste may be stored,
buried, or just dumped on the ground. Eventually these chemicals and waste seep into our groundwater.
Cars and factories pollute the air with smoke and exhaust. Some of the harmful gases they release include
sulfur dioxide (SO2) and nitrogen dioxide (NO2). These gases mix with water vapor in the air and fall back
to earth as acid rain. Acid rain contaminates everything it falls on: soil, water, and plants. The chemical
composition of rivers and lakes may change and become toxic to plants and animals. Acid rain is so
harmful it even damages the buildings it falls on!
Agriculture creates pollution, too. Pesticides (chemicals that kill insects and rodents) and herbicides
(chemicals that kill plants) applied to cropland wash off during rains. They are carried by rainwater to
streams and rivers. Like all chemicals in water, they also may seep through the soil into groundwater.
All the wrappers and packaging from everything we use ends up in landfills. Human garbage includes
plastics, Styrofoam, paper dyed with chemicals, paint cans, rusty cars and lots more. Through time,
rainwater wears away at our garbage sitting in landfills. Eventually these chemicals and waste seep into
our groundwater.
Chemicals that reach our drinking water can make us sick. Contaminated water can lead to headaches,
dizziness, liver problems, and cancer. Disinfection bi-products are added to the water at water treatment
facilities, these are necessary to make the water safe for us to drink, but they have been known to cause
cancer in large amounts. The more contaminated our water is, the more disinfection bi-products need to
be added.
Very small organisms that live in estuaries, such as algae and bacteria, may not be able to survive in
contaminated water. If they do not survive, the organisms that eat them cannot survive (and the
organisms that eat those organisms cannot survive, etc.).
Larger organisms, such as fish and shrimp, may be able to survive in contaminated water. However,
pollution may affect their ability to reproduce. If animals cannot reproduce, their populations may go
extinct.
October 27, 2008
Eating contaminated animals may make humans and other animals sick. Chemicals become more
concentrated as they move up a food chain.
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Name __________________
Seatwork Assignment

Please complete problems on a separate piece of loose leaf paper and attach this
sheet to the front.
1) Determine the molar mass of the following elements
a) Cesium Cs
b) Gold, Au
c) Hydrogen, H2
2) Determine the molar mass of each of the following compounds
a) NO3
b) Al2S3
c) FeSO4
3) What is the mass in grams of 8.52 mol of each of the following substances
a) H2O
b) NiCl2
4) What is the amount in moles of 342.5 g of each of the following substances?
a) Ncl3
b) Ca(NO3)2
5) Express the following as molar amounts.
a) 10.00 g CO2
b) 14.00 g Cr(OH)3
6) A student writes down the following information
- Mass of beaker = 52.43 g
- Mass of beaker and CuSO4 = 65.41 g
7) A student uses a graduated cylinder to measure 25.5 mL of water at 25 Celsius. The
density of water is 1.00g/mL at 25 Celsius.
a) What is the mass of the water in the graduated cylinder?
b) What amount of water, in moles, is in the graduated cylinder?
October 27, 2008
How many moles of CuSO4, did the student add to the beaker?