HOW TO READ CHEMICAL EQUATIONS
UNIT 1
Objectives :






to read chemical equations
to identify elements by their chemical symbol
to count atoms
to identify the coefficients and subscripts in a chemical equation.
to label the reactants and products of a chemical equation
to balance chemical equations
Materials: These account for one complete set. Color scheme is VERY important for
visualization during the activity.
on 3x5 Index
Cards
2 orange 6's
4 red 2's
2 black 7's
4 blue 3's
2 blue "+"
1 black "yield"
sign --->
1 purple
"Products"
4 green 4's
2 purple 5's
1 red
"Reactants"
on 5x8 Index
Cards
Al
C2H6
H2
Al2O3
CaCl2
H2O NaCl P4O10
C
CO2
CH4
Fe
N2 Na2SO4
Fe3O4 NH3
Na
O2
P4
CaSO4 H2O2 Na2O
Pre Lab Questions:
Answer the following before you begin the activity:
5H2
1. What number represents the Coefficient? _____
2. What number represents the Subscript? _____
3. What element is represented by the letter "H"?
_____
4. How many "H's" do you have? _____
Procedure :
1. Using your set of index cards, replicate the chemical equation onto your desk.
2. Label the reactant side and the product side.
Record the following information into Table 1:
3.
4.
5.
6.
Identify the elements on the reactant side.
Count the number of atoms for each element.
Identify the elements on the product side.
Count the number of atoms on the product side.
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7. Are the 2 sides equal? If not, the equation is not balanced.
8. The index cards numbered 2 - 7 are your coefficients. They can ONLY be placed in
front of the elements. You can not change the subscripts.
9. Choose an element that is not balanced and begin to balance the equations.
10. Continue until you have worked through all the elements.
11. Once they are balance, count the final number of Reactants and Products.
12. Write the balanced equation.
13. Can your equation be simplified?
Data :
Table 1 : Chemical Equations (whole page, large boxes, sideways into lab book)
Make the following
Reactants Products Reactants Products
Equations on your desk
- Final
Final
Balanced
Equation
H2 + O2 --> H2O
H2O2 --> H20 + O2
Na + O2 --> Na2O
N2 + H2 --> NH3
P4 + O2 --> P4O10
Fe + H2O --> Fe3O4 + H2
C + H2 --> CH4
Na2SO4 + CaCl2 -->
CaSO4 + NaCl
C2H6 + O2 --> CO2 +
H2 O
Al2O3 --> Al + O2
Analysis/Results:
1.
2.
3.
4.
5.
What does "-->" mean?
What side of the equation are the reactants found? products?
Why must all chemical equations be balanced?
Why can't the subscripts be changed?
What does it mean to "simplify" the equation?
Conclusion:
2-3 sentences on what you learned.
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UNIT 2
Writing Chemical Equations
CHEMISTRY WORKSHEET
Name: _______________________
Write a balanced equation for each of the following:
1. Dinitrogen pentoxide gas in the presence of a platinum catalyst and high enough temperature
forms nitrogen gas and oxygen gas.
__________________________________________________________________________
2. Sulfur solid reacts with iron solid to form solid iron(III) sulfide.
__________________________________________________________________________
3. Hydrogen gas and iron(III) oxide powder react to form liquid water and solid iron powder.
__________________________________________________________________________
4. Magnesium metal reacts with hydrochloric acid to form magnesium chloride solution and
hydrogen gas.
__________________________________________________________________________
5. Magnesium sulfide solid and hydrochloric acid react to form hydrogen sulfide gas and
magnesium chloride solution.
__________________________________________________________________________
6. Oxygen gas reacts with solid copper metal to form copper(II) oxide solid.
__________________________________________________________________________
7. Voltage is applied to two electrodes in a solution of iron(III) chloride and a yellow-green gas
bubbles form on one electrode and metallic deposits form on the other electrode.
__________________________________________________________________________
8. Oxygen gas reacts with hydrogen gas to form liquid water.
__________________________________________________________________________
9. Hydrogen sulfide gas is bubbled through a sodium hydroxide solution to produce sodium
sulfide solution and liquid water.
__________________________________________________________________________
10. Hydrogen gas and aluminum chloride solution are produced when solid aluminum is reacted
with hydrochloric acid.
__________________________________________________________________________
Extra Credit
11. Hydrogen sulfide gas is bubbled through a solution of iron(III) chloride.
__________________________________________________________________________
12. When strongly heated, magnesium sulfide formed a yellow crystalline deposit on the walls of
a sealed reaction vessel. Metallic deposits were found on the bottom of the container.
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UNIT 3
Water-Wine-Milk-Beer
Description
A glass filled with what looks like water is poured into a second glass, where it "magically" turns
into wine. When the wine is poured into a third glass, it changes to milk, and when the milk is
poured into a fourth glass, it changes to beer!
Explanation
The "water" in the first glass is really a solution of sodium carbonate (Na2CO3), also known as
washing soda. The carbonate ion causes the solution to be alkaline, that is, it is a weak base that
produces hydroxide ions (OH-).
The second glass contains several drops of phenolphthalein indicator. An indicator is a substance
that is a different color in acidic solution than it is in basic solution. Phenolphthalein is colorless
by itself, but when the alkaline "water" is poured into the glass, it turns pink, giving a solution
that looks like a light red wine.
The third glass contains a saturated solution of barium chloride (BaCl2). When the "wine" is
poured into the glass, the carbonate ions in the solution react with the barium ions to form
barium carbonate (BaCO3), a white solid precipitate. The suspension of white solid in the
solution makes it look like milk.
The fourth glass contains concentrated hydrochloric acid (HCl) and some bromthymol blue
indicator. When the "milk" is poured into this, the barium carbonate reacts with the acid, forming
soluble barium ions, water, and carbon dioxide gas. The white solid dissolves, the carbon dioxide
creates bubbles, giving the solution a "head," and the bromthymol blue, yellowish-brown in
acidic solution, gives the color of beer.
What We Called It
What Was In the Glass
Chemical Reaction
“water”
Na2CO3(aq)
CO32-
“wine”
phenolphthalein indicator
HIn + OH-
“milk”
BaCl2(aq)
Ba2+ + CO32-
“beer”
HCl(conc) & bromthymol blue
BaCO3(s) + 2H+
H2O + CO2(g)
HCO3- + OHIn- + H2O
BaCO3(s)
Ba2+ +
4
UNIT 4
How to Write a Feasibility Report
A feasibility report examines a problem and its possible solutions. The report determines
how practical the solutions are and what it might cost an organization to implement them. These
types of reports are often used within technical organizations regarding product development.
Difficulty: Moderate
Instructions
Things You'll Need:


Details on the product or project
Information on the alternative solutions
How to Write a Feasibility Report
1.
2.
3.
4.
5.
Create a summary giving an overview of the report.
Create a glossary of terms that will be used within the report.
Write an introduction that tells the purpose of the report.
Discuss all alternatives and options.
Write a conclusion summarizing the entire report and what decision was made from
the conducted research.
6. Write recommendations that give your final solution or opinion.
7. Provide references citing all sources from your research.
8. Write an abstract that includes the problem, methods, conclusions and results of
your report. Since this is a stand alone document, be complete and concise. This will
entice the reader to continue on to the actual report.
9. Place the abstract at the beginning of your paper before the introduction.
10. Create an appendix siting extra information about the report such as books and
websites.
Typical components of a design and feasibility report
1.
2.
3.
4.
Title
Contents
Informative Abstract
Introduction
 Technical Background--Is technical discussion needed in order to make the rest of
the report meaningful to readers
(Remember that this section need not be
included.)
 Background on the situation--How much discussion will you need to explain the
problem, need, or opportunity that has brought about this
report? If there is little
that needs to be said about it, this information can go in the introduction.
5. Discuss the Options--You may also need to provide brief descriptions of the options..
Do not get this mixed up with the comparison which will be in the next section. The
descriptive section provides a general discussion of the options so that readers will
know something about them. The descriptive section does not compare the
options.
It is just a general orientation that gives some brief specifications to the options.
6. Category-by-Category Comparisons--How should you compare the options?
Remember that you write this section so that readers can check your ideas and even
draw different conclusions, if they desire. You would write a section that discusses each
of those points. How should you end the comparative sections? End with a conclusion
that states which option is the best choice in that particular category of comparison.
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7. Conclusions--The conclusion entails summarizing or restating the conclusions you
have already reached in the comparison sections. So, the conclusion section first lists
the simple, single-category conclusions. Then it states the overall conclusion that
balances conflicting single-category conclusions, and ends with a statement that says
which option is the best choice.
8. Recommendation or Final Opinion--What is your recommendation or final opinion?
You would think that that is obvious by now. It should be. Also, the best choice may be
clear but maybe you would not want to recommend it..The recommendation section
should delineate the most important conclusions leading to the recommendation and
then state therecommendation. You may need to recommend several options based on
different possibilities. A good way to handle this is with bulleted lists.Additionally, a
recommendations section includes "recommendations for further action and a listing of
issues that must be resolved before the design can be implemented" (Perelman, 1998,
p. 81).
9. References and notes
10. Appendixes
UNIT 6
What Are Some Careers in Chemistry?
The career options in chemistry are practically endless! However, your employment options
depend on how far you have taken your education. A 2-year degree in chemistry won't get you
very far. You could work in some labs washing glassware or assist at a school with lab
preparation, but you wouldn't have much advancement potential and you could expect a high
level of supervision. A college bachelor's degree in chemistry (B.A., B.S.) opens up more
opportunities. A 4-year college degree can be used to gain admittance to advanced degree
programs (e.g., graduate school, medical school, law school). With the bachelor's degree, you
can get a bench job, which would allow you to run equipment and prepare chemicals. A
bachelor's degree in chemistry or education (with a lot of chemistry) is necessary to teach at the
K-12 level.
A master's degree in chemistry, chemical engineering, or other field opens up far more options.
A terminal degree, such as a Ph.D. or M.D., leaves the field wide open. In the United States you
need at least 18 graduate credit hours to teach at the college level (preferable a Ph.D.). Most
scientists who design and supervise their own research programs have terminal degrees.
Chemistry is a part of biology and physics, plus, there are lots of categories of chemistry! Here's
look at some of the career options related to chemistry:

Chemistry

Ethnobotany

Environmental Law

Patent Law

Technical Writing

Pharmaceuticals

Oceanography

Software Design

Space Exploration

Government Policy

Forensic Science

Biotechnology

Metallurgy

Ceramics Industry

Plastics Industry

Paper Industry

Medicine

Teaching

Engineering

Geochemistry

Agrochemistry

Military Systems
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This list isn't remotely complete. You can work chemistry into any industrial, educational,
scientific, or governmental field. Chemistry is a very versatile science. Mastery of chemistry is
associated with excellent analytical and mathematical skills. Students of chemistry are able to
solve problems and think things through. These skills are useful for any job!
We believe that a Chemical Engineering degree from the University of Waterloo can provide you
an excellent starting point to launch a variety of rewarding careers. Chemical Engineers are at
the forefront of technology and their role in modern society is becoming increasingly important.
Chemical Engineers design, implement and supervise industrial processes where matter
undergoes change. This could be in the pharmaceutical, pulp and paper, food or plastics
industries for example; anywhere where a transformation of matter occurs. Chemical Engineers
also play a major role in the new, emerging field of nanotechnology with applications in the
development of new materials, and devices. They also develop new processes to prevent
pollutants from being released into our environment or to remove them after they are already
there. They decrease our energy use by increasing the efficiency in our fossil fuel refining
plants, or by experimenting with new forms of energy generation and storage. Increasingly
Chemical Engineers are becoming involved in the control, manipulation and production of
biological systems as well, which have many important applications in the area of health care
and food production for example.
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UNIT 5
the BIG KS3 Science-Chemistry crossword on "Simple
Chemical Reactions"
8
Across:
Down:
1 The kind of salt formed from a metal
2 ? acid is well known in the laboratory.
5 Warning of a? (6)
3 Statues made from this might fizz in
dissolving in hydrochloric acid. (8)
6 A very flammable fuel. (6)
7
Another word for burning! (10)
8 The chemical name for gaseous fuel (naturally
from the North Sea!). (7)
10
The formula for water. (3)
(12)
very acid rain! (6)
4 'Not a lot' of reaction with an acid
from this metal. (6)
9 Its the squeaky pop gas! (8)
10 Given out with light in combustion
reactions. (4)
12 You use one of these to test for hydrogen and
11 A moderately reactive metal with
13 This is always formed in a chemical reaction.
14 A powdery rock that fizzes with acids
15 A visual way of displaying lots of results. (5)
16 Definitely applies to your senses when
19
17 Used to test for carbon dioxide. (9)
no spill. (3,6)
(7)
A colourless liquid formed from burning fuels.
(5)
acids and used in batteries. (4)
and makes splended white cliffs. (5)
a fuel gas explodes!
20 A gas formed on burning hydrocarbon fuel.
18 The type of compound formed by
21 When you see this as the end of chemical's
22 General name for a chemical you start
24 A long dead type of fuel! (6)
23 This happens to metals outside and a
25
26 An everyday word for combustion or
(6,7)
name, you know it will bubble with acid! (9)
The fuel for the birthday cake! (6,3)
27 What you see and hear on pouring acid on
marble chips. (4)
28 Used to show what has happened in a chemical
reaction and may not involve any mat5hs! (8)
29 The element that is in most fuels and it makes
up most of coal and coke. (6)
30 This type of element reacts with acids to form
hydrogen in the process. (5)
33 This gas is in air and reacts with fuel molecules
combining an element with oxygen. (5)
with. (8)
bit faster with salty water! (7)
desire! (7)
27 Something that is burned to produce
heat energy. (4)
31 This type of chemical readily reacts
with many metals. (4)
32 A kind of equation with no symbols in?
(4)
34 The formula for carbon dioxide. (3)
in combustion. (6)
35 A fuel from photosynthesis, come on, chopchop! (4)
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