Introduction to Stoichiometry
Authors of original unit: Jerod Gross, Nancy Dailey, Susan House, and Paula Cory
(Hereafter, known as Team 3)
Authors of spin-off: Team 3, Hareesh Gadde, Katti Jablenski, Anne Baranger
Partner Projects: Institute for Chemistry Literacy & Computational Science
(ICLCS), UIUC Dept. of Chemistry, College of Medicine, National Center for
Supercomputer Applications (NCSA), A-C Central School district #262, ROE #38.
Textbook Sources for Adaptations:
“Chemistry.” Wilbraham, Antony C. et.al. Prentice-Hall, Inc.: Menlo Park,
CA. 2002.
DeCoste, Don, Zundahl, Zumdahl. World of Chemistry. Houghton Mifflin, 2007.
“Holt Chemistry.” Holt, Rinehart & Winston: Austin, TX; 2006; p. 301.
“Holt Chemistry: Resource File Ch. 9.” Holt, Rinehart & Winston: Austin, TX.
2006.
“Stoichiometry Balloon Races.” Irene Cesa, Sr. Ed. Flinn ChemTopic Labs,
Vol. 7. Flinn Scientific, Inc.: 2002; pp. 72-74.
Intended Audience: Chemistry I students
Keywords:
Subject area: stoichiometry, limiting reagents
Unit Keywords: molar ratio, stoichiometry, limiting reagents, excess
reagents, conversion, factors, molar mass, balanced
equations, mole
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Summary of the Module:
Rationale:
This is not a complete instructional unit. It is meant as an introduction to the topic
of stoichiometry, concluding with an introduction to limiting reagents as a possible
extension. Given the amount of trouble students typically have in learning
stoichiometry, the pace of this module is intentionally slow. Students will sharpen
their skills at using ratios, conversion factors, mole conversions, and balancing
equations. Certain prior knowledge is assumed. By now, students should have been
balancing equations, using the mole concept, balancing equations, converting units,
and calculating gram-molecular masses.
Use(s) of the module:
 Reinforce use of ratios as in molar ratios
 Design their own data tables
 Reinforce use of conversion factors
Illinois Learning Standards:
 11.A.4a-d,f
 11.A.5a-d
 11.B.4c
 11.B.5c
 12.C.5a
Software needed and other hardware/software needs:
 Web browser
 Flash player; Shockwave (?)
 Excel (creating tables for data); PowerPoint
 SMARTBoard with DLP and Internet connection if do not have computer
lab access (Optional: LCD projector; elmo camera, or whatever your
screen projection capability is); screen
Content of the Module:
Introduction: The following is a suggested sequence for this module. Time
required will depend on your students and class schedule.
©2011 University of Illinois Board of Trustees • http://islcs.ncsa.illinois.edu/copyright

Day One: Non-Chemical Stoichiometry
o Objective: Calculate quantities on nonchemical reactions
o Equipment: Nuts, Bolts, projector, Web Browser; Excel
o Activity: Nuts & Bolts of Stoichiometry (dry lab)
o Assignment: Lab report (use your own format) (OPT)
o Assignment: Recipe Assignment
Day Two: Stoichiometry (mostly mol)
o Objective: Calculate quantities in chemical reactions
o Handout on conversions (opt)
o Equipment: Projector and screen; Web browser and internet
access; PowerPoint
o PowerPoint: “Stoichiometry” (slides #1-9)
http://iclcs.uiuc.edu/moodle/file.php/7/moddata/forum/58/6272/
Stoichiometry_pp.ppt
o Animation: Formation of Water
http://www.visionlearning.com/library/flash_viewer.php?oid=1858&mid=56
o Activity: In-Class problems (“Introduction to Stoichiometry
Problems”)
o Assignment: Practice Problems (“Stoichiometry Assignment”)


Day Three: Stoichiometry (Mass  Mass)
o Objective: Calculate quantities in chemical reactions
o PowerPoint: “Stoichiometry” (slides #10-11)
o Equipment: Computer lab with Internet access (opt: projector and
screen); PowerPoint
o Activity: In-Class Combustion Problems (“Combustion of
Hydrocarbons”)
o Animation: Combustion of Hydrocarbons
http://www.chem.iastate.edu/group/Greenbowe/sections/projectf
older/flashfiles/stoichiometry_excess_oxy.html
o Assignment: Practice Problems (“Sample Problems”)

Day Four: Wet Lab
o Objective: Measure mass of product and compare theoretical
calculation.
o Equipment: Chemicals, balances, etc., as required for desired lab
that might go with your text book.
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
o Possible stoichiometry labs include:
 2Fe(s) + 3CuCl2(aq)  3Cu(s) + 2FeCl3aq)
 SrCl2(aq) + NaCO3(aq)  2NaCl(aq) + SrCO3(s)
 “Stoichiometry Balloon Races”
o Assignment: Lab Report (use your own format)
Day Five: Volume-Volume Stoichiometry
o Objective: introduce vol-vol stoichiometry
o Equipment: computer, projector, screen, PowerPoint
o PowerPoint: “Stoichiometry” (slides #12-16)
o Assignment: Use your own textbook’s problems

Day Six: Extension (Optional)
o Objective: Introduction to Limiting and excess reagents
o PowerPoint: “Stoichiometry” (slides # 17-21)
o Equipment: Computer Lab with internet access; web browser
(projector & screen, opt); Power Point
o Animation: Limiting & Excess reagents for specified reactions
http://www.chemcollective.org/applets/stoich.php
o Activity: “Introduction to Limiting & Excess Reagents”
(see URL under ‘animation’ above)

Day Seven: Extension continued (Optional)
o Equipment: items per lab group: 5 1-L clean soda bottles, vinegar,
baking soda, 5 round balloons, 5 ring stands, cloth tape measure
o In-class Activity: Limiting Reagent Introduction (wet lab); may be
done as a demonstration
o Assignment: Lab Report (use your own format)

Day Eight: Assessment
o Short Quiz (or your own textbook quiz)
Description of Each Day:
Day One: The first day is simply to introduce the student to the concept of
stoichiometry in a nonchemical fashion. The objective is to allow the student to
calculate quantities and ratios, especially if the student is weak at this skill. A
“dry lab” is available where the student will use Excel to create a data table.
©2011 University of Illinois Board of Trustees • http://islcs.ncsa.illinois.edu/copyright
Day Two: The second day is to start the stoichiometry process by calculating
molar ratios and basic conversion set-up. A PowerPoint presentation is used to
show some background on the mole and how it is used in these calculations. The
student will be doing in-class problems and as an assignment. There is a conversion
handout that is available. An animation on the formation of water is also shown.
Day Three: On this day, the student is introduced to mass-mass type of
calculations. From the PowerPoint presentations, several more slides are shown to
help the student’s understanding. An interactive website is used by individuals (or
as a class, depending on computer access) that shows mass-mass reactions.
Day Four: On this day, it is time for a “wet lab.” Here, the student can actually
use chemicals and the lab of the teacher’s choice, based on preference and their
text. Three possible labs are suggested. From this activity, the student will
prepare a lab report according to the teacher’s format.
Day Five: On the fifth day, the student is introduced to volume-volume
stoichiometry. For this, the teacher will use their own materials and text.
Day Six: On the sixth day, an extension lesson is offered. The topic here is that
of Limiting Reagents. An interactive activity is available, which can be done as
individuals or as a class, depending on computer access. The last few slides of the
power point can also introduce the student to actual and per cent yields (optional).
Day Seven: Today a wet lab, or demo, is done pertaining to limiting reagents.
Students should write a lab report according to the teacher’s format.
Day Eight: On the last day, a short quiz is given where the student has to balance
equations and do various stoichiometric calculations.
©2011 University of Illinois Board of Trustees • http://islcs.ncsa.illinois.edu/copyright