Wet Lab:
Determining the Empirical Formula of Magnesium Oxide
Course: SCH3U
Unit: Quantities in Chemical Reactions
Lesson: Designing experimental strategies for determining the empirical formula
of magnesium oxide
Modified from: Mustoe et al., (2001) Chemistry 11. Toronto: McGraw-Hill Ryerson Ltd. p.212
OVERARCHING QUESTION
- How are quantitative concepts in chemistry (E.g. mole, molar mass and empirical formula) related and
how can health care professionals apply these concepts to develop drugs using quality-controlled
procedures?
BIG IDEAS:
MATERIALS:
- Relationships in chemical reactions can be described quantitatively.
- The efficiency of a chemical reaction can be assessed by applying
concepts such as the mole, molar mass and empirical formula.
- Health care professionals use these concepts to synthesize drugs in safe
and efficient ways.
MINISTRY EXPECTATIONS:
Scientific Investigation Skills
A1.1, A1.2, A1.4 Formulate relevant scientific questions, select
appropriate instruments, Apply knowledge of safe laboratory practices
A1.5 Conduct inquiries to collect observations and data, compile
accurate data from laboratory, organize and record the data
A1.8 Synthesize, analyze, and evaluate data
A1.11 Communicate ideas, plans, procedures, results and conclusions
orally, in writing, using appropriate language and a variety of formats
A1.13 Express the results of calculations involving data accurately
A2.1 Identify and describe a variety of careers
Relating Science to Technology, Society, and the Environment
D1.1 Analyze processes in the home/workplace that involve chemical
quantities and calculations (E.g. Health care professionals are expected
to calculate dosages of prescription drugs accurately and safely)
Developing Skills of Investigation and Communication
D2.1, D2.2 Use appropriate terminology, conduct an inquiry to
calculate the percentage composition of a compound
D2.4 Determine empirical/molecular formulae
D2.7 Conduct an inquiry to determine the actual yield, theoretical yield,
and percentage yield of the products of a chemical reaction
Understanding Basic Concepts
D3.3 Explain relationship between the empirical formula and the
molecular formula of a chemical compounds
Electronic Balance x2
Sandpaper square x12
8cm strip of magnesium
ribbon x12
Laboratory/Bunsen burner x12
Sparker x12
Retort stand x12
Ring clamp x12
Clay triangle x12
Crucible with lid x12
Crucible tongs x12
Ceramic pad x12
500 ml wash bottle x12
~6L of distilled water (dH2O)
1L disposal beaker
Goggles x24
Glass rod x12
Note: Materials and chemicals
listed below are for 12 groups
of 2 students each (24 students
total). Prior to the experiment,
ensure electronic balances are
adjusted correctly for
weighing, crucibles are clean
for proper execution of
laboratory exercise, and wash
bottles are filled with distilled
water.
STUDENT LEARNING GOALS:
APPENDICES
1. Students learn to develop strategies for solving calculation questions Wet Lab – Handout package
2. Students apply calculation strategies properly using correct units and (teacher copy)
mathematics
Wet Lab - Handout package
(student copy)
PRIOR KNOWLEDGE:
 Mole conversions using molar mass and Avogadro’s number
 Calculations using percent yield
 Knowledge of experimental apparatus and WHMIS
PART
T/L STRATEGIES
ACTION Apparatus Design (Day 1):
- Students review concepts about the production of magnesium oxide and calculating
60 min. empirical formula
- Determine apparatus for measuring empirical formula
Conduct Experiment (Day2): Students conduct inquiry, and critically analyze results
Recommendations (Day3): Students write recommendation letter justifying their claims
Inquiry/Research Process and Scientific Method will guide students on how to implement a
proper laboratory experiment and evaluate the findings. Students will develop higher-order
thinking skills through synthesis of information collected, formulating conclusions, and
transfer of prior knowledge and skills to a new situation. They will perform observations,
analyze quantitative data, and explain their results using prior knowledge and formulas. This
model will aid students in developing and promoting information literacy skills.
The Problem-Based Model will help make this laboratory experiment more relevant to
students. The lab incorporates a social and cultural concern of high consumption of carbonated
drinks (connection to STSE) that can be a cause of stomach ulcers. This model brings together
the Ontario curriculum and a real-life issue that will help students extend their knowledge
beyond the classroom. Students will determine how stomach ulcers arise and develop a
protocol for creating an antacid medication to help solve this issue.
Assessment
Students will be provided with a handout to be completed prior to the lab. This handout contains
scaffolding questions to help students organize the information in a clear, logical manner. It will include
questions to assess prior knowledge of chemical reactions and quantities in chemical reactions (AfL).
Students will also be responsible in developing a protocol on how to determine the empirical formula of
MgxOy(s). To be inclusive of multiple abilities, they will decide how to present the procedure; for
example, a visual format (ex. a flow chart and diagram of the apparatus) or a series of written steps.
Students will then compare their protocol with the protocol provided by the teacher and make the
necessarily adjustments (AaL). This handout will help students self-assess what they already know and
what they should improve on to successfully carry out the experiment
During the lab, students will be making observations and recording data. They will use this information to
answer several questions directly related to the experiment. All components of the experiment (i.e. student
handout, data collection, and data analysis) will be collected by the teacher for evaluation (AoL) – see
attached rubric for more details. This experiment will allow the teacher to assess students’ knowledge and
application of empirical and molecular formulas.
Teaching Notes
This laboratory experiment fits into the Quantities in Chemical Reactions unit plan after students
have a clear understanding of mole conversions, molar mass and empirical formulae concepts.
Students continue to build on this existing knowledge in a laboratory setting in order to solidify
and contextualize their theoretical knowledge. First, students design and implement a procedure
for determining the empirical formula of MgO(s) so that they build additional inquiry skills that
allow them to solve empirical formula-based problems through experimentation. They not only
have to calculate the empirical formula of a compound quantitatively using mole conversions but
they must also interpret their results, suggest sources of error, and reflect scientifically on the
strengths and weaknesses of their procedure. Second, students directly link their prior
knowledge to practical, real-world issues by applying their skills to antacid production in the
pharmaceutical industry. This contextualization helps students make sense of their learning and
creates a more engaging classroom environment where students can draw on their own
experiences.
TEACHER KNOWLEDGE, SKILLS AND PREPARATION NEEDED:
Background Knowledge: Combustion is a reaction of oxygen in the air with a sample of matter.
In this experiment, the empirical formula of magnesium oxide will be determined. This
experiment covers two main areas:
i. Law of conservation of mass  total mass of the products of the reaction must equal the
total mass of the reactants
ii. Law of constant composition any potion of a compound will have the same ratio of
masses as the elements in the compound
The empirical formula of a compound gives the simplest positive integer ratio of atoms of each
element found in a compound. The molecular formula, on the other hand, identifies the number
of each type of atom found in the molecule.
In this laboratory, the magnesium strip is oxidized by oxygen in the air to produce magnesium
oxide. Since the air also consists of nitrogen, the magnesium also produces magnesium nitride.
Although nitrogen is fond in higher amounts in the air than oxygen, magnesium reacts with less
nitrogen than oxygen because oxygen is more reactive. In this experiment there is a purification
step to remove any magnesium nitride formed. This is done by washing the product with distilled
water and further reheating it. The water converts the magnesium nitride to magnesium
hydroxide and ammonia gas. By further heating the product, water is removed and the
magnesium hydroxide is converted back to magnesium oxide. The unbalanced equations of the
reactions are as follows:
Mg (s) + N (g) + O2 (g)  MgO (s) + Mg3N2 (s)
MgO (s) + Mg3N2 (s) + H2O (l)  MgO (s) + Mg(OH)2 (s) + NH3 (g)
MgO (s) + Mg(OH)2 (s)  MgxOy (s) + H2O (g)
Assessment: Teacher should make sure to check and verify student’s protocol for carrying out
the lab. Give student the ‘correct’ procedure so that they can compare and correct any mistakes
and forgotten steps. Make sure students follow the correct procedure.
Safety: Students should be following the following safety precautions at all times during the
experiment:
- Eye protection at all times – do NOT look directly at the burning magnesium
- Open flame so be aware and cautious
- Do not breathe in the fumes generated after heating
- Do not place anything hot on the balance
- Use tongs when handling anything hot such as the crucible, lid, triangle, ring and stand
Disposal: All contents are safe to be disposed of into the garbage bins.
LABORATORY SET-UP AND CLASSROOM FLOOR PLAN
Distribution of materials: The materials required for this lab are located in the labelled
cupboards beneath lab bench stations 1 and 2. Bunsen or laboratory burners are located beneath
lab bench station 3. All safety equipment (ex. gloves and goggles) is located beneath lab bench
station 12. Students are responsible for obtaining and returning these materials to their
appropriate place.
Sandpaper squares and electronic balances will be supplied by the teacher and will be available
on the teacher’s desk. Students are not to remove the balances.
A disposal beaker (1L) labelled “Chemical Waste” will be placed in the fume hood. Beakers are
located beneath bench station 11.
Distribution of chemicals: Magnesium ribbon strips and 500 ml wash bottles with distilled water
(dH2O) are to be supplied by the teacher and will be distributed at the teacher’s desk.
Student workspace: Each pair of students will be assigned a workspace according to the
numbered bench stations (see laboratory floor plan below)
Name: _________________________________________________
Date: ______________________________________
SCH3U Chemistry Laboratory: Determining the Empirical
Formula of Magnesium Oxide
Introduction
THE PROBLEM
o Research has found that more and more high school students at University of Toronto
Schools are consuming highly acidic foods and drinks (E.g. carbonated beverages) that are
causing an increased incidence of ulcers. In fact, so many students are developing ulcers
that pharmaceutical companies are struggling to keep up with demands for antacid
medications.
THE SOLUTION
o The team: The Grade 11 class from UTS
o The motto: We don’t get ulcers. We give them.
o The mission: Develop and test a protocol for making high quantities of the antacid,
magnesium oxide, or MgO(s).
o The task: Imagine that you are a lab technician at the pharmaceutical company, Merck
Frosst. Due to high demands, the company has procured large amounts of solid magnesium
metal, Mg(s) and needs to convert it to MgO(s) in the most efficient way possible. You are
responsible for developing, testing, and analyzing a protocol for making MgO that you can
propose to the Merck Frosst CEO, Kenneth Frazier.
STAGE 1. PLANNING AND INITIATING
o Design a protocol for making MgO(s) from Mg(s)
o Determine factors important for creating MgO(s) from Mg(s)
o Identify materials/apparatus needed
o Identify potential safety hazards
o Verify that the product created has the empirical formula, MgO
o Note: This portion of the lab must be verified by your teacher BEFORE
proceeding to Stage 2: Implementing and Executing
STAGE 2. IMPLEMENTING AND EXECUTING
o Execute the protocol created in Stage 1 with modifications from the teacher
o Follow appropriate safety guidelines
STAGE 3. ANALYSIS AND RECOMMENDATIONS
o Analyze the data collected to determine if the product created has the
empirical formula, MgO
o Answer discussion questions
o Write a 250-word letter to the president of Merck Frosst
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
STAGE 1: PLANNING AND INITIATION
A. What do I know already?
1. What is the PURPOSE of this experiment:
The purpose of this experiment is to determine the empirical formula of MgO.
2. The process by which an element combines with oxygen to form an oxide is called
[oxidation]
. (Hint: See Nelson textbook on p. 200)
3. Fill in the following table to determine the reactants and products of the reaction.
REACTANTS
What reactant is Merck Frosst SUPPLYING?
[Mg(s)]
What other reactants are NEEDED to make MgO?
Where might you be able to obtain this reactant?
PRODUCTS
What is/are the desired
PRODUCT(s)?
[MgO(s)]
[O2(g), atmosphere]
4. Using the reactants and products from the above table, write a balanced chemical
equation for the desired reaction.
[2Mg(s) + O2(g)  2MgO(s)]
5. The oxidation of solid magnesium ribbon occurs very slowly at room temperature –
too slow for industrial purposes. How might this reaction be sped up so that it is useful
for Merck Frosst? What equipment would be needed?
[Add heat = combustion of magnesium = bunsen burner]
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
B. How will I design a protocol for making MgO(s) from Mg(s)?
6. Using the information from Questions 1-5, MAKE A LIST OF MATERIALS that you
think you will need to create MgO(s) from Mg(s). Consider chemicals, apparatus, safety
equipment, etc.
Bunsen Burner
Flint
Electronic balance
Retort stand
Ring clamp
8 cm strip of magnesium ribbon
Goggles
Crucible tongs
Ceramic pad
Distilled water
Wash bottle
Clay triangle
Crucible with lid
Sand paper/emery paper
7. Now it is time to DEVELOP A PROTOCOL.
a. OPTION A: Draw and label a diagram to illustrate the apparatus needed for
this reaction to proceed.
b. OPTION B: Write out a procedure to illustrate the steps needed for this
reaction to proceed. Attach this on a separate sheet of paper.
8. CONSIDER SAFETY PRECAUTIONS: What safety precautions and safety equipment
will you need when performing this experiment?
Equipment:
Safety Precautions:
Disposal:
Safety goggles, lab coat
Do not breathe fumes generated
Once burner is lit, assume all equipment is hot.
Handle equipment with tongs
Never place anything hot on a balance
Dispose of the MgO in a beaker designated by
teacher
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
C. How will I verify that the product has the empirical formula,
MgO?
It is possible that the protocol designed in Part A will cause Mg and O2 to combine in a ratio
that does not give you MgO. For example:
Mg(s) + O2(g)  MgxOy (s)
where x and y are unknown
How could you determine the empirical formula of the product? Develop a protocol by
considering the following questions:
1. What quantities can you measure for your product MgxOy(s) and your reactant Mg(s)?
[The mass of each]
2. Can any of these properties be measured? If so, how?
[Yes, by using an electronic balance]
3. If we assume that none of the magnesium is lost (ie. We start and end with the same
weight of magnesium) and the weight of our product is higher, what atom is
contributing the extra weight?
[The oxygen]
4. If we know the mass of the magnesium and the molar mass of the magnesium, what
can we calculate?
[The number of moles of magnesium in our product]
5. Can you also calculate your answer to 4. but with oxygen?
[Yes]
6. Can you compare the quantities of magnesium and oxygen that you would obtain in 4.
and 5.? If yes, how does this help you figure out the empirical formula of the product?
[Yes. If they are the same then there is a 1:1 ratio of Mg to O in the product and the
empirical formula would be Mg(s) + O2(g)  MgO (s). However, if you have twice as
many moles of O in the product as the Mg then it would be a 1:2 ratio and the empirical
formula would be Mg(s) + O2(g)  MgO2 (s).]
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
STAGE 2: EXECUTING AND IMPLEMENTING
You have now completed Stage 1: Initiation and Planning and have developed a protocol for
creating MgO(s) that has been verified by your teacher.
D. What steps am I missing in my protocol?
Next, compare the protocol that you developed to the protocol listed below. What steps were
similar between the two procedures. What steps were different? Use the following table to
make assess how complete your protocol is (AaL).
Similarities between your
procedure and the sample
procedure provided
Steps missing in your
procedure that should be
added
Steps that should be removed
from your procedure
- collect apparatus (Bunsen
burner, magnesium, flint,
tongs, electronic balance)
- using the balance, measure
and record the mass of the
magnesium strip
- light the Bunsen burner and
burn the magnesium strip
- weigh the remaining
magnesium oxide
- 8cm magnesium strip,
crucible with lid, ceramic
plate, sand paper, distilled
water, clay triangle, glass
rod)
- using sand paper, clean the
magnesium strip to remove
any oxides
- measure the empty crucible
with the lid and record, also
measure the crucible with
the magnesium strip added
and record
- burn the magnesium until
the magnesium ignites and
cover the crucible with the
lid as soon as it ignites for
one minute (repeat this until
the magnesium no longer
ignites)
- when the magnesium no
longer ignites, heat heat the
magnesium for another 45mins
- use a glass rod to crush up
the contents
using distilled water, wash off
the glass rod and boil until all
the water is evaporated
- place the magnesium into a
beaker and heat
- burn the magnesium for 5
minutes
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
Sample Protocol
Materials:
Bunsen Burner
Flint
Electronic balance
Retort stand
Ring clamp
8 cm strip of magnesium ribbon
Goggles
Crucible tongs
Ceramic pad
Distilled water
Wash bottle
Clay triangle
Crucible with lid
Sand paper/emery paper
Safety Precautions:
Wear goggles when burning the magnesium; use tongs to remove the hot crucible; do not
breathe in the fumes produced; do not place anything hot on the balance
Apparatus:
Procedure:
1. Assemble the apparatus as shown in the diagram.
2. Obtain a strip of magnesium and clean it using sandpaper or emery paper to remove
any coating of oxide on the strip.
3. Using the electronic balance, measure and record the mass of the empty crucible and
lid and record the mass in the table below. Then, add the magnesium strip to the
crucible and record the mass of the crucible, lid and magnesium strip in the table
below.
4. Remove the lid and place the crucible with the magnesium strip on the clay triangle.
Light the Bunsen burner and heat the crucible with a strong flame. Using the crucible
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
tongs, hold the lid and as soon as the magnesium ignites (CAUTION), cover the
crucible with the lid. Continue to heat for about 1 minute.
5. Carefully remove the lid (CAUTION). Heat the crucible until the magnesium ignites
once more and again quickly cover the crucible. Repeat this heating and covering until
the magnesium strip no longer ignites. Heat for another 4-5 minutes with the lid off.
6. Using the crucible tongs, place the crucible on a ceramic plate to cool.
7. When the crucible is cool enough to touch, put it on the bench and carefully grind up
the product into small particles using the glass rod. Rinse the glass rod with distilled
water into the crucible to remove any particles remaining on it.
8. Make sure to add enough distilled water to the crucible to wet all the contents. This
white product is magnesium oxide. The yellowish-orange product is magnesium
nitride. *
9. Return the crucible to the clay triangle and place the lid slightly ajar. Heat the crucible
gently until the water begins to boil and continue to heat until all the water is
evaporated and the product is completely dry. Remove the crucible with the tongs and
place it on a ceramic pad to cool.
10. Using the tongs, carry the crucible to the electronic balance and measure and record
the mass of the crucible, lid and magnesium oxide in the table below.
11. Put the magnesium oxide in the disposal beaker provided by your teacher. DO NOT put
it in the garbage or sink.
Note: When weighing out the magnesium ribbon, make sure the mass is at least 0.10g
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
E. What do I observe when I carry out the experiment?
Use the following observation table to tabulate the results of your experiment.
Mass of clean, empty crucible and lid
Mass of crucible, lid and magnesium strip
Mass of crucible, lid and magnesium oxide
13.8g
14.0g
14.1g
F. How should my data be analyzed?
ANALYSIS QUESTIONS:
1. a) Using the mass of magnesium strip used and magnesium oxide produced, calculate
the mass of oxygen that reacted with the magnesium.
Mg (s) +O2 (g)  MgO (s)
(0.2g) + (0.1g)  (0.3g)
Mas of Oxygen that reacted with magnesium = (Mass of magnesium oxide produced,
crucible and lid – mass of magnesium, crucible with lid)
= 14.1g – 14.0g
= 0.1g
b) Using this experimental data, calculate the percentage composition of the
magnesium oxide.
Experimental percentage composition of Mg =
(mass of Mg used/mass of Mg0 produced) x 100%
= (0.2g/0.3g) x 100%
= 66.6%
= 67%
Experimental percentage composition of O2 =
(mass of Mg used/mass of Mg0 produced) x 100%
= (0.1g/0.3g) x 100%
= 33.3%
= 33%
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
c) Determine the experimental empirical formula of magnesium oxide (assume a 100g
of MgO). Note: round your empirical formula to the nearest whole number ratio e.g.
1:1, 1:2, 2:1 or 3:3
Ratio of Magnesium:
Mass of Mg = 67g
Molar mass of Mg = 24 g/mol
Number of moles = mass/molar mass
= 67g/(24g/mol)
= 2.791 mol
Ratio of O2:
Mass of O2 = 33g
Molar mass of O2 = 16g/mol
Number of moles = 33g/(16g/mol)
= 2.062 mol
Determining ratio:
O2 = (2.062mol)/(2.062mol) = 1
Mg = (2.791mol)/(2.062mol) = 1.35 = 1
Therefore the ratio is 1:1 and the empirical formula is MgO
2. a) Before moving on, verify your empirical formula with your teacher and use the
empirical formula of magnesium oxide to determine the theoretical mass percent of
magnesium in magnesium oxide.
Theoretical molar mass of MgO = 40g/mol
Molar mass of Mg = 24g/mol
Percentage composition = (molar mass of Mg/molar mass of MgO) x 100%
= [(24g/mol)/40g/mol] x 100%
= 60% Mg
b) Determine your percent yield by calculating the difference between your actual
mass percent of magnesium (AP) and your experimental mass percent of magnesium
(EP) using the following formula:
Percent error = (EP-AP) x 100%
AP
= [(67%-60%)/60%] x 100
= 11.7%
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
3. a) Why did we put water in the crucible and then evaporate it completely? What
purpose does this serve? (Hint: Think of what other byproducts were in there)
Since the air is composed of not only Oxygen and there is a large component of
Nitrogen, the nitrogen also reacts with the magnesium to form Mg3N2 (magnesium
nitride). Adding water to the crucible serves as a purification process because the
nitrogen reacts with the Hydrogen in the water to produce ammonia gas and the
remaining magnesium then reacts with more oxygen
b) Why was magnesium nitride (Mg3N2) produced as well as magnesium oxide (MgO)?
Because the air is comprised of not only oxygen but also a large component of it is
nitrogen as well so some of the nitrogen also reacts with the magnesium to produce
magnesium nitride
c) Would you expect more magnesium nitride (Mg3N2) to be produced or more
magnesium oxide (MgO) to be produced? Why?
Although there is more nitrogen present in the atmosphere, more magnesium oxide
with in fact be produced because oxygen is more reactive than nitrogen.
4. a) What are some sources of error in this experiment? (list at least 2)
1) Not all the magnesium was burned. 2) Some magnesium oxide smoke escaped
during the reaction.
b) How could these sources of error be reduced/how did we try to reduce these
sources of error?
1) By burning it multiple times until didn’t any more. 2) Putting the lid on as quickly
we could when the reaction began.
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
G. What recommendation should I make?
TASK:
Write a 250-word letter (maximum) to the president of Merck Frosst outlining the need for
antacids and the solution that you developed. Make a recommendation on whether or not you
think your solution will be effective and support your recommendation with evidence.
Be sure to include a short description/explanation of the following:
- What antacids are used for? (Why do we need them?)
- What you did to produce an antacid?
- What the antacid you produced is?
- Do you think this will be effective? (Why or why not?)
- Give at least one piece of evidence to support your claim
Dear Merck Frosst,
It has come to my attention that, due to the rising number of stomach ulcers arising
from acid reflux, we are in dire need of more antacid medicine that can be made relatively
inexpensively and in large quantities. I’m sure you know that magnesium oxide acts as an
antacid and is therefore able to fill this need. Thus, my class and I have developed a procedure
for manufacturing magnesium oxide (MgO) by only using magnesium (Mg), heat, air, and
water. We have ensured that only MgO is produced and that any impurities (such as
magnesium nitride) have been removed through a purification step with water.
There are many pros and cons to using this to produce antacids. The first is that it is
relatively inexpensive as the only material you need to purchase is magnesium. Moreover, if
one can obtain a large quantity of magnesium and equipment it is possible to produce this in
large quantities. However, the only drawback in using magnesium oxide as an antacid is that it
is not supposed to be used repetitively and can be used as a laxative as well
(http://www.nlm.nih.gov/medlineplus/druginfo/meds/a601074.html). That being said, it is
still used as a viable antacid thus, I believe this is an effective way to fill the need for antacids
to battle stomach ulcers.
Sincerely,
Student
PS See enclosed for procedure outline
H. References
Mustoe, F., Jansen, M. P., Doram, T., Ivanco, J., Clancy, C., & Ghazariansteja, A. (2001).
Chemistry 11. (pp. 212-213). Toronto,ON: McGraw-Hill Ryerson Limited.
SCH3U Quantities in Chemical Reactions (Teacher Copy)
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Name: _________________________________________________
Date: ______________________________________
I. Rubric (Pre-lab, Protocol Design, Recommendation Letter)
Categories
50-59%
(Level 1)
Knowledge and Understanding
Knowledge of
The student
content
demonstrates limited
knowledge about
empirical formulas,
balancing equations
and is unable to
answer questions
about determining
empirical formulas
Understanding
of content
60-69%
(Level 2)
70-79%
(Level 3)
80-100%
(Level 4)
The student
demonstrates some
knowledge about
empirical formulas,
balancing equations
and is able to answer
some questions about
determining empirical
formulas
The student
demonstrates
considerable
knowledge about
empirical formulas,
balancing equations
and is able to answer
most questions about
determining empirical
formulas correctly
The student
demonstrates
considerable
understanding about
determining empirical
formulas
The student
demonstrates a high
degree of knowledge
about empirical
formulas, balancing
equations and is able
to answer almost all
questions about
determining empirical
formulas
The student
demonstrates a high
degree of
understanding about
determining empirical
formulas
The student uses
planning skills with
considerable
effectiveness and the
information is
organized in an orderly
way
The student uses
processing skills with
considerable
effectiveness and
shows creativity and
detail to the protocol
design
The student used
critical/creative
thinking processes
with considerable
effectiveness in the
protocol design
The student uses
planning skills with a
high degree of
effectiveness and the
information is very
organized and easy to
follow
The student uses
processing skills with a
high degree of
effectiveness and is
very creative with a lot
of detail in the protocol
design
The student used
critical/creative
thinking processes
with a high degree of
effectiveness in the
protocol design
The student expresses
and organizes ideas
and understandings
with considerable
effectiveness and the
recommendation letter
contains all required
sections but the
student does not
answer all required
questions effectively
Expresses and
organizes ideas and
understandings with a
high degree of
effectiveness and the
recommendation letter
contains all required
sections and address
all required questions
effectively
The student
demonstrates limited
understanding about
determining empirical
formulas
The student
demonstrates some
understanding about
determining empirical
formulas
The student uses
planning skills with
limited effectiveness
and the information is
not organized in an
orderly way
The student uses
planning skills with
some effectiveness
and the information is
organized but it fairly
disorganized
Use of
processing
skills
The student uses
processing skills with
limited effectiveness
and shows little or no
creativity and detail to
the protocol design
The student uses
processing skills with
some effectiveness
and shows some
creativity and detail to
the protocol design
Use of
critical/creative
thinking
processes
The student used
critical/creative
thinking processes
with limited
effectiveness in the
protocol design
The student used
critical/creative
thinking processes
with some
effectiveness in the
protocol design
Thinking
Use of
planning skills
Communication
Expression
The student expresses
and
and organizes ideas
organization of
and understandings
ideas
with limited
effectiveness and the
recommendation letter
does not contain all
required sections and
does not address all
required questions
The student expresses
and organizes ideas
and understandings
with some
effectiveness and the
recommendation letter
contains most of the
required sections but
does not address all
required questions
SCH3U Quantities in Chemical Reactions (Teacher Copy)
16
Name: _________________________________________________
Communicatio
n for different
audiences and
purposes
Date: ______________________________________
The student
communicates for
different audiences
and purposes with
limited effectiveness
and writes the
recommendation letter
in an inappropriate
tone
The student
communicates for
different audiences
and purposes with
some effectiveness
and writes the
recommendation letter
in a somewhat
appropriate tone
The student
communicates for
different audiences
and purposes with
considerable
effectiveness and
writes the
recommendation letter
in an appropriate tone
The student uses
conventions,
vocabulary, and
scientific terminology
with limited
effectiveness
throughout the
experiment
The student uses
conventions,
vocabulary, and
scientific terminology
with some
effectiveness
throughout the
experiment
The student uses
conventions,
vocabulary, and
scientific terminology
with considerable
effectiveness
throughout the
experiment
The student applies
knowledge and skills in
familiar contexts with
limited effectiveness
and was unable to
design a correct
protocol
The student applies
knowledge and skills in
familiar contexts with
some effectiveness
and was able to design
some correct steps for
the protocol
The student applies
knowledge and skills in
familiar contexts with
considerable
effectiveness and was
able to design a
correct protocol
Transfer of
knowledge
and skills
The student transfers
knowledge and skills
to new contexts with
limited effectiveness
and shows no signs of
applying knew
knowledge to design a
protocol
The student transfers
knowledge and skills
to new contexts with
some effectiveness
and shows some signs
of applying knew
knowledge to design a
protocol
Making
connections
within and
between
various
contexts
The student makes
connections within and
between the results
obtained in the lab and
theory learned in class
with limited
effectiveness
The student makes
connections within and
between the results
obtained in the lab and
theory learned in class
with some
effectiveness
The student transfers
knowledge and skills
to new contexts with
considerable
effectiveness and
shows signs of
applying knew
knowledge to design a
protocol
The student makes
connections within and
between the results
obtained in the lab and
theory learned in class
with considerable
effectiveness
Use of
conventions
Application
Application of
knowledge
and skills
SCH3U Quantities in Chemical Reactions (Teacher Copy)
The student
communicates for
different audiences
and purposes with a
high degree of
effectiveness and
writes the
recommendation letter
in a very appropriate
tone
The student uses
conventions,
vocabulary, and
scientific terminology
with a high degree
effectiveness
throughout the
experiment
The student applies
knowledge and skills in
familiar contexts with a
high degree of
effectiveness and
designed a protocol
that was very accurate
correct
The student transfers
knowledge and skills
to new contexts with a
high degree of
effectiveness and is
very effective in
applying knew
knowledge to design a
protocol
The student makes
connections within and
between the results
obtained in the lab and
theory learned in class
with a high degree of
effectiveness
17