The Plight of Onondaga Lake
Dun, Dunnn, Dunnnnnnn………
Everyone take a seat and get ready for the NEW SEMESTER!
Blog Assignments
 Each Sunday, Holt will post 2 questions about the topics
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being covered in class.
You will have until Wednesday at 12:00 midnight to respond
to them.
Some of the questions will be based on a calculation, some
will be based on some conceptual understanding and some
will be based on your opinion.
But you must base your opinion on some fact and list it.
Generally, I question will be a calculation-type question and
the other will be one of opinion, based on research.
Example of this might be…
Holt Post: Do you think that acid rain is a problem in the
U.S.?
Student Post: No, I think that acid rain is a myth brought out
by the media to scare us.
Blog Assignments
 If this was your post, you would receive very little
credit (if any).
 I am not interested in your opinion, unless you back
it up with something.
 Now, some questions I post for you might be of a
topic of which you have no opinion.
 The reason you have no opinion, is because you
know little to nothing about that topic.
Blog Assignments
 So, what I want you to do is do a little research on
the topic, get both sides of an argument and give
me your opinion after you have reviewed the topic.
 This is why I am giving you Sunday, Monday,
Tuesday and most of Wednesday to respond.
 Then you will have until Saturday at midnight to
read a few of your classmate’s responses and
comment back to them.
 You may agree or disagree but again you need to
support your position with fact or your opinion
based on documented fact.
 You will not need to respond to the calculation-type
questions.
Blog Assignments
 Grading—this weekly assignment will constitute your journal part
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of your portfolio and ½ of your HW grade for a total of 15% of your
total grade.
Below is the rubric for this grading…
Respond to Post on Time
10 pts
Answer to calculation problem is correct
10pts
Opinion response is documented with
class notes or website
10pts
Response to classmate is coherent
and documented
10 pts
Response is free of grammatical errors
10 pts
 There is no partial credit for any of the categories listed above. So,
1 misspelled word earns you a 40/50 at best.
Blog Assignments
 You may continue to do the normal journals for 2%
EXTRA CREDIT added to your score at the end of the
semester.
 However, you may not miss a day and they must be
written perfectly. There is no partial credit for extra
credit.
Labs
 We will run our labs like a professional lab.
 I will be the “lab supervisor” and you all will be the employees.
 Think of your grades as your paycheck. Each member of the
group starts with 10 points for the lab write up (book) and 10
points for laboratory technician behavior.
 Each infraction below results in losing 1 point for lab technician
behavior. The lab book will be graded as follows…pre-lab
questions (2), introduction (2), materials and methods (2), data
recording/graphs/tables (2) conclusion including post lab
questions (2).
 If you do not bring your lab book to class or you do not have the
introduction written or you are not using the lab book
throughout the lab, you will lose the points associated with the
mistake—2 points if there is no intro, 2 points if you are not
writing down the procedures as we go and 2 points if you are not
writing data as we go.
Labs
 Each group (department) will be led by a team leader who will be in charge of
the rest of the group.
 Your job will be to keep your team in line, assign tasks and come to the
supervisor (me) when needed.
 If team members are not working or straying to other groups or being loud—
you and your team will all lose points.
 Your team may not come and talk to me and they may not ask me questions.
 It is your job to make sure that your entire team understands the lab and what
we are trying to accomplish in the lab.
 I will come around and ask your team and you questions about the lab.
 If a team member that I choose cannot answer the question, your team will be
penalized.
 It is also the team leader’s responsibility to explain the lab to the entire class
when picked to do so.
 The tasks being assigned by the team leader will be gathering equipment,
gathering chemicals, labeler, experimenting, collecting data, interpreting lab
and explaining steps to group and cleaning up.
Labs
 The equipment gatherer must get the needed beakers, thermometers, hot
plates, etc as needed and put them back in their places after they are cleaned.
 If equipment is left at your station or put away dirty the leader and equipment
person will lose points.
 The chemical gatherer must get the necessary chemicals used in the lab.
 They must not take the chemicals from the prep table back to your table.
 If any chemicals leave the lab table, your team will lose points. (The leader and
the chemical person.)
 The labeler’s job is to make certain that all chemicals are labeled at your
station.
 If the supervisor comes to your lab station and there are any beakers, test tubes,
etc ,that have chemicals (including water) and they are not labeled, you will
lose points. (The leader and the labeler.)
 The experimenter is the person that carries out the experiment.
 I would suggest that everyone be involved in this even though one person is
truly responsible for this.
 However, if the experiment is not going as planned or there are mistakes,
broken glassware, spills, etc, the leader and experimenter lose points.
Labs
 Along with the experimenter there will be a main data collector.
 Each person should be collecting data in their own books, but if I come
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around, I will mainly look for the main data collection book or paper
and check it.
The chosen data collector must produce this from their book or paper
in their handwriting or the leader and data collector loses points.
There is also a person that is in charge of explaining the steps of the
lab and interpreting the data throughout the experiment.
This person should know what is going on before it happens and be
able to explain what the results mean.
They are responsible for making sure that each member totally
understands what is expected and what is meant in each step.
If I come by and ask anyone in the group what is going on or what just
happened or what was supposed to happen and they are unable to do
it, that person the leader and the explainer all lose points.
Labs
 The clean up person is in charge of clean up.
 The chemical person is to dispose of the chemicals and the equipment person
takes care of the equipment, but the clean up person makes sure that the table
and sink are in perfect condition before the group goes back in to the room.
 Failure to do so costs each person in the group points.
 You will notice that there are 7 jobs not including the leader of the group.
 The leader may pick one of the 7 jobs to do along with their leadership duties,
however, no more.
 The leader is really in charge of all the jobs being carried out.
 But they are there to make sure that everything is being done by all, not doing
it all themselves.
 I will be watching closely to make sure that the leader isn’t hogging the jobs
and that the workers are working hard so that the leader needs to pick up the
slack to save them.
 Everyone must work as a team doing their own jobs. A group cannot do all the
jobs together—someone must be in charge of each task.
 Also there must be a sheet taped to your stations with the names of the group
and jobs for each. If there is not a sheet taped to each station, then the entire
team loses points.
Labs
 At the end of the lab, each member of the group is to comment
on how the behavior and work ethic of each member enhanced
the productivity of the lab.
 Were your group members
 helpful or not,
 did they take care of their responsibilities,
 were they actively involved in the experiment and
 either answering questions or asking questions for clarification.
 You are looking to come up with at least 2 positive things each
group member did and 1 thing they need to improve upon next
time.
 These are strictly confidential and will only be seen by me.
 You will receive a copy of these comments when you turn in your
completed lab write up.
Environmental Chemistry
 One of the hottest topics in today’s world is
environmental chemistry.
 Topics considering pollution, recycling, ozone layer
depletion, alternative fuels and global warming are all
around us—newspapers, magazines, CNN, and regular
cable TV discuss the possibilities of these
environmental factors.
Environmental Chemistry
 What does the Bible state about our stewardship
toward the environment? Are we following God’s plan?
 I am not going to tell you what to think about today’s
environmental issues—enough people do that.
 But I am going to ask you to think.
 I want you to have your own opinions about this
before the end of the school year.
Environmental Chemistry
 I have spoken to many educated people about Global
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Warming and the Environment and their responses
range from…
“I don’t care cuz I can’t change it” to…
“There is no problem, it’s all a scam” to…
“There is a problem, but I don’t know how to fix it” to…
“There is a huge problem and if we don’t fix it, the
Earth is toast.”
But most of them have no background evidence to
support their thoughts or…
They only look at one side of the argument.
Environmental Chemistry
 However, they act as though they know so much about the topic
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because they spout off the most.
This is annoying to me and…
You are going to be different.
I don’t care what your position is as long as you can back up your
thoughts and you have looked at arguments for and against your
initial beliefs.
It is probably best to have no pre-conceived ideas at this point
although that is going to be difficult.
Environmental Chemistry
 We are going to use documented environmental issues
to learn chemistry for the rest of the year and shape
our belief system of the environment of which we live..
Are There Problems at Onondaga Lake?
We are going to take a deeper look at solution
chemistry through a case study of Onondaga Lake
in Syracuse, NY.
Get Sheets over by the window—it’s a Graph
and the Solvay Process! Whoo-Hoo
HW: Look up and define the
characteristics of an unsaturated,
saturated and super-saturated
solution.
Onondaga Lake
 In 1847, the mayor of a middle-sized city in a developing
country shared his vision for the lake adjoining his
municipality. Read what he had to say about his nice, little
town…
 Our beautiful lake will present continuous villas ornamented
with shady groves and hanging gardens and connected by a
wide and splendid avenue that shall encircle its entire waters
and furnish a delightful drive for the happy and prosperous
citizens of the town who will, towards the end of each
summer’s day, rush to it for pleasure, relaxation or
improvement of health.
--Harvey Baldwin
Onondaga Lake
 This indeed was the scene in Syracuse, NY on the
banks of Lake Onondaga. The area prospered as a
number of 5 Star hotel resorts dotted the shoreline,
the citizens of the area rushed to it for play, and a
thriving fishing industry sprang up.
 But in 1920, the fishing industry and resorts were
gone. The fish taken out of this lake are no longer
allowed to be eaten. You are not allowed to swim in
the cloudy waters. The city of Syracuse does not
draw its water from this lake for human usage.
 Lake Onondaga is now called one of the world’s
most polluted lakes and the most polluted lake in
the country.
Onondaga Lake
 At first glance this may seem like a problem only to
the residents near the lake in Syracuse, but it is not.
 This is an account of a typical risk/benefit dilemma
that many other societies faced in the past are now
facing or will face in the future.
 Initially technology brought new opportunities and
new prosperity to the shores of Lake Onondaga,
but environmental deterioration began to negate
those advantages—it is an account of
industrialization on a developing society.
 What went wrong?
Onondaga Lake
 This story of salt, soda and Syracuse is on of
industrial development, environmental impact and
technology’s response.
 It begins with a look at the rich natural resource of
the brine springs that made Syracuse an ideal
location for chemical manufacturing.
 There was an increasing need for sodium carbonate
(soda ash) that was plentiful in this area.
 With this great natural resource a chemical
procedure called the Solvay Process was used to
extract this compound.
Onondaga Lake
 This process was revolutionary for its time and was
considered to be environmentally responsible.
 However, over the years of using this process, a
great amount of unused by-products began to
wash into the lake and contribute to its
contamination.
 Along with the Solvay process, the chlor-alkali
process, developed to produce chlorine and sodium
hydroxide, released large quantities of toxic
mercury to the already troubled waters.
 These two processes along with an old way of
wastewater treatment system, caused the lake to
end up in the poor shape that it is today.
Onondaga Lake
 Onondaga Lake is about 4.5 miles long and 1 mile
wide. Muskegon Lake is 5.5 miles long and 2.2 miles
wide.
 It has an average depth of about 35 feet. It drains
into the Seneca River which empties into Lake
Ontario.
 The relatively small size misrepresents its importance.
 It provides a textbook case of the impact of industrial
processes on the environment and society.
 The Native Americans were the first to discover the
springs of brine (concentrated solutions of sodium
chloride) that are common in this area.
Onondaga Lake
 By around 1800, almost all of the salt used in the
U.S. came from this area.
 Two methods were used to produce salt along
the shores of the lake.
 The brine was boiled down in large iron kettles
heated by wood fires.
 As the water evaporated, the solution became
more concentrated.
Onondaga Lake
 At the saturation point, the crystals began to
form on the surface of the liquid and on the
sides of the containers.
 The salt was removed with large wooden
scoops and placed in baskets to dry.
 However, as the forests were cleared for
farmland and burned for fuel, the cost of this
method became too expensive.
Onondaga Lake
 Then they moved to a solar process where the sun
evaporated the brine to reveal the salt crystals.
 However, salt mines were discovered in the west
and in other more sunny areas of which took over
the salt yards and by 1926, the last of the Onondaga
salt yards closed.
 However, before the salt mines had closed a
process was discovered whereby sodium carbonate
was made from sodium chloride.
 Sodium carbonate is used in the manufacturing of
soap, paper, water softeners and glass.
Onondaga Lake
 Even today sodium carbonate ranks 11th among
industrial chemicals produced.
 As a water softener, the carbonate ion (CO32-)
reacts with calcium and magnesium ions in a
double replacement reaction whereby insoluble
CaCO3 and MgCO3 are formed and settle to the
bottom of the tank.
 In the very early days sodium carbonate was
produced by extracting the ashes of seaweeds.
Onondaga Lake
 This was a tedious process and the demand for
this product was much greater than what could
be produced. Enter…technology.
 In 1865 Albert and Ernest Solvay came up with a
way to manufacture sodium carbonate from
sodium chloride.
 The Solvay Process starts with two of the
cheapest and most abundant chemicals in the
Earth’s crust: NaCl and CaCO3.
 The overall reaction is
 2NaCl + CaCO3  Na2CO3 + CaCl2
Onondaga Lake
 The starting materials for the Solvay Process were
available in abundance near Syracuse.
 For this reason it is not hard to understand why in
1884, the Solvay Process Company began making
sodium carbonate along the Onondaga.
 In fact, from 1960 to 1985, 2000-2800 tons of
Na2CO3 were produced daily by Allied Chemical
Company, the successor to the Solvay Process
Company.
 This booming industry gave the residents jobs,
great public schools with extensive athletic, music,
art and other extracurricular activities—even
dental care was free for students.
Onondaga Lake
 However, with time, it became obvious that the Solvay
Process was also contributing some less desirable byproducts to the town and to Lake Onondaga.
 One key point is that the reaction above does not occur
directly.
 If you mix NaCl, CaCO3 and water, the NaCl would
dissolve and the CaCO3 would not.
 No reaction would take place and no sodium carbonate
would be formed.
 A series of reactions with a variety of by-products
would need to be made to get to the end product.
Onondaga Lake
 Some of those by-products are NH3, NH4Cl, CaO,
Ca(OH)2, CO2 and NaHCO3.
 A particularly crucial step involves four of these
compounds.
 It is the reaction that occurs when CO2 and NH3
are bubbled through a salt solution at 0°C.
 NH3(g) + CO2(g) + NaCl(aq) + H2O(l) NaHCO3(s) + NH4Cl(aq)
 In this equation we see that sodium bicarbonate is
produced as a solid and ammonium chloride is
produced dissolved in solution.
Onondaga Lake
 Both of these chemicals form in the water solution,
but under these cool conditions the solubility of
the NaHCO3 is less than that of the NH4Cl.
 The solubility curve of these two compounds show
this phenomenon.
 The line for each shows the amount of compound
that will dissolve per 100mL of water solution.
Onondaga Lake
 You can see that at all temperatures the
ammonium chloride will dissolve more solid than
sodium bicarbonate.
 So at 0°C the solubility of NH4Cl is about
30g / 100mL whereas the solubility of sodium
bicarbonate is only 7.0g / 100mL.
 This means that the sodium bicarbonate
crystallizes, separating as a solid, while the
ammonium chloride remains behind in solution.
Onondaga Lake
 To illustrate this process of fractional
crystallization, suppose we start with 100mL of a
solution containing 12.0g of NaHCO3 and 24.0g of
NH4Cl at 50°C.
 The solution is cooled to 0°C.
 Only about 7.0g of NaHCO3 will stay in solution
whereas all the NH4Cl will be in solution. So, the
only compound precipitating out will be the
NaHCO3.
Onondaga Lake
 So, the amount of NaHCO3 that crystallizes out
will be 5.0g.
 The percentage that remains in solution is 7.0/12.0
or 58% and the amount that precipitates out is
5.0/12.0 or 42%.
 The solid sodium bicarbonate is filtered out and
then this solid is converted to the desired Na2CO3
by heating it to about 300°C…
 NaHCO3 + heat  Na2CO3 + CO2 + H2O
Time to Put this Solvay process
together…
 Sit down and get out your notes and your solubility
curves and your Solvay Process summary sheets…
 We need to start right away so that we can get through
everything to be ready for our Lab on Friday…
 Write your name on a small piece of paper and give it
to me
Your Turn
 Suppose that 100mL of a solution containing 40.0g
NH4Cl and 10.0g NaHCO3 at 40°C is cooled to 0°C.
Calculate the masses of each compound that would
crystallize and the masses of the two compounds
remaining in the solution. Would this be a good
method for obtaining pure NaHCO3?
The Solvay Process Summary
 We want this reaction (we want sodium carbonate)…
 NaCl + CaCO3  Na2CO3 + CaCl2
 But the Solvay process had to get around the insolubility of
calcium carbonate.
 step (1) calcium carbonate (limestone) is heated…
 CaCO3 + heat  CaO + CO2
 step (2) ammonia, CO2 from step 1, salt and water react…
 NH3 + CO2 + NaCl + H2O  NaHCO3 + NH4Cl
 Step (3) sodium bicarbonate is heated…
 2 NaHCO3 + heat  Na2CO3 + H2O + CO2
 step (4) the ammonium chloride and calcium oxide react…
Not re-used
 2 NH4Cl + CaO  2 NH3 + H2O + CaCl2
Your Turn
 If in this step, 34.5g of NaCl was used in excess NH3,
CO2 and H2O, how much solid NaHCO3 and solid
NH4Cl would be produced?
 How much Na2CO3 would be produced from the
previous amount in step 3?
Today in Chem
 Sit at your desk and quickly contemplate the life of a
ground hog. This should only take about 5-10sec.
 Next, get out your solubility curve, Solvay Summary
sheet and your notes.
 Take out a sheet of paper—not part of your notes and
get ready for a quiz…
 I want to show you a video of a cool Friday Fire
experiment I would like to try tomorrow because lab
went so well on Friday…
 If you bring in supplies—you can play with the fire.
 If not, you can just watch.
Surprise Quiz (no talking—you
have 8 minutes to turn this in…)
 Let’s say that you were working for the Solvay company
and Big Man Solvay wanted to test your understanding
of his system.
 He looks you square in the face and says, “OK Mr./Ms.
Smarty Pants. If I used 30.0g of pure sodium chloride,
how much sodium bicarbonate could I make? At what
temperature would I need to carry this out to get pure
SB and how much pure SB would I make? How much
sodium carbonate could I make in step 4 from this
amount of sodium chloride?”
Review Questions from Some HW
 ___ ___________ solution is one in which more solute
could still be added.
 ___ ___________ solution is one in which no more
solute could be added at this temperature and dissolve.
 ___ ___________ solution is on in which more solute
was forced into the solution by adding heat and then
slowly cooling it down so that the solute stays in the
solution.
 If the solution is cooled rapidly, or it is disturbed, the
solute will come out.
Back to Notes on Onondaga Lake
 From what we have stated thus far, it would seem
that the Solvay Process would be an ideal example
of enlightened chemical manufacturing.
 Two cheap and plentiful naturally occurring
substances—salt and limestone—are converted
into two useful products—sodium carbonate and
calcium chloride.
 However, CaCl2 is not in as demand as Na2CO3.
Onondaga Lake
 CaCl2 is used in concrete mixtures, to melt snow
and ice and in certain solar heating units to name a
few.
 But over the years the sales of calcium chloride
from the Onondaga plant did not keep pace with
the sales of sodium carbonate.
 The excess calcium chloride was allowed by state
and federal regulations to be dumped in solution
into a tributary of the Onondaga Lake.
Onondaga Lake
 Also large amounts of unmarketable salts were
dumped into solitary marshes along the coastline
of Onondaga Lake—up to 500 tons every day.
 It was mostly CaCl2 but also some un-reacted NaCl
and CaSO4.
 However, calcium, sodium and chloride ions
leached from the marshes by rainwater into the
lake.
Onondaga Lake
 In 1943 a barrier holding back a waste bed
measuring 70 feet high and covering 400 acres of
area broke and released a flood that buried over 20
houses.
 Most of the substances in the waste beds are ionic
compounds.
 Their water solubility is very important to the
composition of Onondaga Lake.
 Some salts including NaCl and CaCl2 are water
soluble—others such as CaCO3 are not.
Onondaga Lake
 The following solubility rules will help us
understand which ionic solids are generally
soluble in water and which ones are insoluble in
water.
1. Salts containing Group 1 metals and the
ammonium ion are soluble in water.
2. Salts containing nitrates and acetates are soluble
in water.
Onondaga Lake
3. Salts containing halogens (except F) are soluble
in water unless they are combined with Ag, Hg or
Pb.
4. Salts containing sulfates are soluble in water
unless they are combined with Ag, Hg, Pb, Sr, or
Ba.
5. Salts containing sulfides, oxides, phosphates,
carbonates and hydroxides are insoluble unless
with Group 1 metals and NH4+.
Your Turn
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1.
2.
3.
4.
Using the solubility rules, determine if the following
salts are soluble…
Magnesium hydroxide
Barium sulfate
Lithium carbonate
Strontium nitrate
Onondaga Lake
 Solubility rules also help us predict the reactions that
occur when solutions containing certain ions are
mixed.
 This information, in turn, helps us understand the
chemistry of Lake Onondaga.
 For example, over the years large amounts of water
soluble NaCl and CaCl2 made their way into the lake.
 Also large amounts of CO32- are found in the lake.
Onondaga Lake
 When Ca2+ ions enter the lake and combine with CO32
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ions, insoluble CaCO3 is formed in the lake.
Ca2+(aq) + CO32-(aq)  CaCO3(s) is a net ionic equation.
NIE only show the ions that combine to make a reaction.
Other ions are present in the solution but stay as ions. They
are called spectator ions because they are not participating
in the reaction.
The deposition of CaCO3 in the lake has increased the
sedimentation rate of the lake and a large CaCO3 delta
exists where Ninemile Creek flows into the lake.
In short, Lake Onondaga is a saturated solution of CaCO3.
HW: What is a delta? Are deltas harmful?
Life in Chem for Today…
 Lab Talk
 Tough Quiz
 EZPZ Notes of Net Ionic Equations
 Work on HW (NIE) or Make Some Fireballs (if
you have material—you can make some, if
not, do your HW and see fire near the end of
class)
 Lab write ups are due on Thursday—along with peer
Lab
Talk
review.
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You need Intro, Mat/Methods, Data Table, Conclusion.
Remember, in the conclusion you will need
to summarize the key parts of the experiment
to decide whether your experiment has supported your
hypothesis or not. So, restate your hypothesis and state
how it has or has not supported it with data
 Use the post-lab questions throughout the lab to
further explain your understanding of the lab
 Explain if you believe any errors were made, and how
they could be avoided in future labs—what was difficult
that you think others might need to watch for when
they try your lab?
 It is your goal as a scientist to make the most amount of
Na2CO3 as possible from the Solvay Process.
 Each day you obtain 100kg
of NaCl
free of charge.
Tough
Quiz…
 You buy ammonia for 12 cents per gram from a local
manufacturer and you have free water and free CO2, as well.
 You are able to sell your sodium carbonate for 13 cents / gram.
 If the process takes 4 hours to complete for 50 workers
making $25 per hour each, plus $800 per hour operating costs.
How much money can you make in an 8 hr work day?
 Holy Baloney, Mr. Holt! How do I start this?
 Hint: How much NaHCO3 and NH4Cl can be made?
 Hint: How much NH3 is needed?
 Hint: This all takes place in a 350L tank. How much NaHCO3
dissolves in that much water at 0ºC?
 You do the rest…
Chem Today…
 “The (wo)man who knows how, will always
have a job. The (wo)man who knows why, will
be the first (wo)man’s boss.”
 Yah, baby, ponder that!
 Talk about yesterday’s BEAST problem.
 Talk about Question #1 blog thoughts.
 Notes on Net Ionic Equations
 HW on Net Ionic Equations
Beast Problem Revealed…
 The amount of NaHCO3 produced is roughly 144,000g.
 The amount of NH3 used is roughly 29,000g.
 Solubility of SBC at 0ºC is 7g / 100mL.
 We have 350L or 350,000mL so FL or prop gives us…
 24,500g of SBC that will dissolve.
 144,000g produced – 24,500g still in sol’n = 119,500g solid
 119,500g SBC produces roughly 75,000g Na2CO3 that we sell.
 We sell 75,000g of SC at 13 cents / g or $9750.
 We bought 29,000g NH3 at 12 cents / g for $3480.
 50 workers at $25 / hr for 4 hours (1 batch) = $5000.
 4 hours of operating cost at $800 / hr = $3200.
 Total cost = $11680 for 1 batch (4 hour period)
 Total $$ brought in for sales of SC = $9750
 Net = -$1930 per 4 hour batch or -$3860 per 8 hour day.
 Here is blog
your typical
employee stats scaled down to a salary
Your
answers…
of $100…
 Home mortgage = $30
 Car payments = $15
 Utilities = $5
 Food = $15
 Gas and Misc. expenses = $20
 Credit Cards = $15
 Total expenses = $100, subtracted from their take home pay
leaves $0 for savings.
 Is this what you tell them... “Too bad, so sad, you got into
this mess, so it is your fault.”
 If you cut
their salary
by 30-40%, what would happen to
Your
blog
answers…
them?
 Ask your parents how your lives would change if their
employer told them they were going to cut their salary by
30-40%?
 Typical (not all) people live just above their wages—even
owners of businesses.
 If you get a raise…you buy a bigger house, car, coat, cabin,
etc.
 For those of you that answered that you would take a pay
cut as the big boss…could you, if you lived just above your
means?
 Not in
the notes…
Net
Ionic
Equations…
 Writing net ionic equations.
 Write a balanced chemical equation as normal.
 Look at each compound to determine if it breaks up in

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
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solution (soluble) or remains as a solid in water.
Use solubility rules for ionic compounds.
Liquids and gases do not break up in solution. (These will
be molecular compounds).
Break up strong acids…
HCl, HBr and HI are strong (know them).
Acids with 2 or more oxygen than hydrogen are strong.
HNO3?
H2SO4?
HClO2?
 Soluble or not?
NIE
 NaBr
 Write as broken up ions…
 Na+ + Br What about CaCl2?
 Ca2+ + 2Cl How about HNO3?
 H+ + NO3 And finally, AgBr?
 It is insoluble so leave it alone—AgBr
 Write the net ionic equation for silver nitrate solution
NIE
reacting with copper (II) chloride solution.

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AgNO3 + CuCl2 
DR
AgNO3 + CuCl2  Cu(NO3)2 + AgCl
Balance…
2AgNO3 + CuCl2  Cu(NO3)2 + 2AgCl
AgNO3 is soluble
2Ag+ + 2NO3- + CuCl2  Cu(NO3)2 + 2AgCl
CuCl2 is soluble
2Ag+ + 2NO3- + Cu2+ + 2Cl-  Cu(NO3)2 + 2AgCl
Cu(NO3)2 is soluble
2Ag+ + 2NO3- + Cu2+ + 2Cl-  Cu2+ +2NO3- + 2AgCl
 AgCl is insoluble
NIE
 2Ag+ + 2NO3- + Cu2+ + 2Cl-  Cu2+ +2NO3- + 2AgCl
 Cross out spectator ions—the ions that stay
the same on both sides of the equation.
 Write the ions and compounds that
remain…
 2Ag+ + 2Cl-  2AgCl
 Reduce coefficients if possible.
 Ag+ + Cl-  AgCl
 Write in states.
 Ag+(aq) + Cl- (aq) AgCl(s)
Today in Chem…
 Go over a bit of the HW.
 Quiz collected for HW grade (you be the
engineer).
 No giving up on the quiz—you can pout
or get mad at me, but you cannot quit!
 If a solution of lead (II) nitrate was mixed
Quiz
for
HW
with a solution of potassium iodide, what
would the net ionic equation look like?
Pb(NO3)2 + 2KI  PbI2 + 2KNO3
Pb2+

+
Pb2+ NO3NO3Pb(NO3)2
Pb2+ and 2NO3-
K+
K+
II-
KI
K+ and I-
NO3-
INO3-
I+
K+ PbI2 K
 Question 2 is a bit tougher…
 Think for
about HW
the Solvay Process and all the steps that
Quiz
must occur to produce and recover and re-use
materials.
 It is your job to come up with a sketch for a Solvay
Plant that will produce Na2CO3.
 Explain each step of the process…
What else reacts in this tank?
Where does it come from?
NH3 bubbled in 
NH3 gas tank
NaCl in
water
What is made in this tank?
Where does it go?
What else is being made at other points in
this process?
What are the temperatures of the tanks?
Today in the Life of an Honors
Chemistry Student…

Take a graded quiz
 Notes on Concentration
 Next Lab Handout
Quiz
magnesium sulfide + nitric acid
2. chromium (III) nitrate + barium metal 
3. potassium phosphate + aluminum nitrate 
1.
Concentration
 Qualitatively, the concentration of a solution can be
said to be strong or weak.
 However, chemists want to be a bit more accurate in
their description…so they use a quantitative
measurement.
 In general concentrations are measured as the amount
of solute dissolved in a certain amount of solvent.
 You already know about molarity.
 Molarity is the moles of a solute in a liter of solution.
Concentration
 If you added 5.0g of sodium bicarbonate to a 100.0mL
solution what would the molarity of that solution be?
Mole Fraction (X)
 Mole fraction (actually written as a decimal) is the
moles of solute (or solvent) / total number of moles in
the solution.
 If you mixed 2.0 moles of NaCl in 7.0 moles of water,
the mole fraction of solution that is NaCl is…
 2.0 moles NaCl / 9.0 moles all = 0.22 NaCl
 You can also say that the mole fraction that is water is
0.78.
Mole Fraction
 If you added 5.0g of sodium bicarbonate to a 100.0mL
of water, what would the mole fraction of NaHCO3 of
that solution be? (Density of water is 1.0 g/mL)
Riddle…
 Hello. I am about 8.5” wide and 11” long. I am white
with a lot of black dots on me. I am sitting with my
twin brothers and sisters next to the overhead
projector. Please pick me up, take me home, read me
and do as I say. Bring back your responses tomorrow
for the really cool guy in the front to see. What am I?
 Hello. There are 3 parts to me. One is very EZ, the
second is a little tougher and the 3rd part of me is
quite a thinker. I am very good for you, although you
don’t like me most of the time. You will need a sheet
of paper, a calculator, your periodic table and notes to
fully understand me. Get ready for me. What am I?
Today’s Quiz
(2 EZs  and a Thinker)
1. Write a net ionic equation for a solution of aqueous
cobalt (II) chloride reacting with sodium hydroxide…
2. What mass of solid AgBr is produced when 100.0mL of
0.150M AgNO3 is added to 20.0mL of 1.00M NaBr?
3. A nearby lake may be polluted with Pb2+ ions. How
might you test the concentration of lead (II) ions in
this lake?
The Lab





The goal of the lab was to create a solubility curve for
KNO3.
The point at which you noticed crystals is called the
saturation temperature.
This is the temperature at which no more solute
(KNO3) can stay in solution.
You found 6 saturation temperatures that you must
put on to an Excel chart.
The x-axis is temperature (ºC) and the y-axis is the
amount of KNO3 in g that can dissolve in 100g of
water.
The
Lab
 Example: if your data showed the crystals began to




form at 67ºC for the test tube with 1.8g of KNO3 in
2.5g of water, how much KNO3 could dissolve in 100g
of water?
Answer: 72g
So, on your chart at the 67ºC mark you would create a
point at 72g.
Do this 5 more times and draw the curve for your
chart.
Get the “real” curve from a source on-line and paste
both in your lab books—call one Figure 1 and the
other Figure 2.

Quiz (1Q over net ionic equations)
Notes on concentration
Lab books due Thursday
Mid Chapter Quest on Friday (Onondaga, Solvay, Net
Ionic Equations, Concentrations, Solution Stoich and
Solution preparations / dilutions)
Then next week, Friday, we will have another end of
Chapter Quest—these 2 quests will be averaged into
one quest.
If God exists, does it matter if I believe it?
If God doesn’t exist, does it matter how much I
believe that He does?
Today’s
Agenda






Today’s Quiz
1. Write a net ionic equation for a solution of aqueous
iron (III) chloride added to an aqueous solution of
sodium sulfide.
Review Mole Fraction
 If you added 15.0g of sodium chloride to a 100.0mL of
water, what would the mole fraction of NaCl of that
solution be? (Density of water is 1.0 g/mL)
 moles of NaCl = 0.256 mol
 moles of H2O = 5.56 mol
 mole NaCl / total moles = X
 0.256 / 5.816 = 0.044 = XNaCl
% Concentration
 If you want to know the concentration as a percent by
mass you need a couple of things.
 The first is what mass of solute you have and the other
is the mass of water you have.
 % by mass = (mass solute / mass solution) x 100
 So, if you added 3.5g of NaCl to 96.5g of water you
have a solution that is 3.5% NaCl by mass.
 This means that of the total mass of the solution, 3.5%
of it is NaCl.
% Concentration
 If you added 5.0g of sodium bicarbonate to a 100.0mL
of water, what would the percent by mass of NaHCO3
of that solution be?
Molality (m)
 Molality (m) is another measurement for
concentration.
 It is similar to molarity (M).
 Molarity is moles solute / L solution
 Molality is moles solute / kg solvent
 So, if we have 0.30 moles of CaCl2 in 500.0g of water,
we have a concentration that is…
 0.30 mole / 0.500kg or 0.60m
Concentration
 If you added 5.0g of sodium bicarbonate to a 100.0mL
of water, what would the molality of that solution be?
Parts per million (ppm)
 Often when the concentration of a solution is very
small, the previous methods do not look as nice.
 So, in these cases ppm or ppb are used.
 Parts per million (ppm) tell you how many parts are
present in a million total parts.
 Percent by mass is really pph (parts per hundred).
 If the % was 3.5%, that means that there are 3.5 parts
per 100 total parts.
 You may use particles, ions, molecules, moles or grams
to figure ppm or ppb.
Parts per million (ppm)
 If you added 5.0g of sodium bicarbonate to a 100.0mL
of water, what is the concentration of NaHCO3 in
ppm?
 We have 5.0g per 105 total grams or 4.8% or 4.8pph.
 Set up a proportions of 4.8 / 100 = x / 1,000,000
 Solve for x to get…
 48,000 ppm
Parts per million (ppm)
 If you added 0.0025g of sodium bicarbonate to a
100.0mL of water, what is the concentration of
NaHCO3 in ppm?
Diluting a Solution
 Sometimes you have a solution already made that is
too concentrated to use for an experiment.
 How is a solution diluted?
 The equation used to determine how to prepare a
solution by dilution is…
 c1V1 = c2V2
 c1 = concentration of the more concentrated solution
 V1 = volume used of the more concentrated solution
 c2 = concentration of the solution you want to make
 V2 = volume of the solution you want to make
Diluting a Solution
 If you need 150.0mL of a 2.5M solution of KNO3 for an
experiment and all you have is a bottle of 6.5M KNO3
solution, how would you make the desired solution.
 We want (c2 and V2)
 c2 = 2.5M
 V2 = 150.0mL
 We have (c1)
 c1 = 6.5M
 We need to use (V1)
 V1 = ??
Diluting
a Solution
 cV =c V
1
1
2
2
 V1 = c2V2 / c1
 V1 = (2.5M ∙ 150.0mL) / 6.5M
 V1 = 58mL—but this is not the answer…
 You were asked “How to make the solution”.
 So, to prepare this solution, you would take a 150mL
volumetric flask and add about 50mL of distilled H2O.
 Then you would add 58mL of the concentrated (6.5M)
solution of KNO3.
 Then you would fill the flask to the fill line with more
distilled H2O.

On a warm and sunny day in Philadelphia you start your new job
for a chemical research company. Your boss is kind of a jerk, but
the pay is good and the benefits are better. As you were gazing
out the window in a dream world, Dr. Smith comes up and asks
you to carry out your first experiment. It calls for a reaction with
100.0mL of 2.0M silver nitrate and 85mL of 3.10M HCl. He points
to a table full of chemicals and grunts—you assume he means to
use these chemicals. So you do. There is a bottle of 12.0M HCl
and a jar of AgNO3 solid crystals.
1. How would you prepare each solution (AgNO3 and HCl)
2. What is the balanced equation?
3. What is the net ionic equation?
4. How much solid product would be made in this reaction?
Your Turn…
 Predict what insoluble precipitates (if any) will form
Your
Turn…again…
when the
following solutions are mixed. Write the net
ionic equation for the precipitation reactions.
 0.10M NaCl and 0.10M AgNO3
 0.10M BaCl2 and 0.10M MgSO4
 0.10M KCl and 0.10M Cu(NO3)2
 Proponents that claim that Onondaga Lake’s amount
of CaCO3 is not a problem state that the excess CaCO3
neutralizes acid rain. Do a calculation to check their
claim that 17,000 tons of CaCO3 could neutralize 3.0
x 1011 L of 0.0005M H2SO4 (acid rain).
Onondaga Lake
 Lake Onondaga is very different from most freshwater
lakes due to its very high concentrations of various
ions.
 A typical lake has sodium ion concentrations below
10ppm and calcium ion concentrations below 50ppm.
 Onondaga Lake has been measured at 550ppm Na+
and 500ppm Ca2+.
 Where HCO3- is the most common anion in most
lakes, Cl- is the most common anion in Onondaga.
 Lake Onondaga also contains sulfate, nitrate, copper,
chromium, cadmium and mercury ions as well.
Onondaga Lake
 This last group of ions originally came from
manufacturing plants along the coast instead of
the Solvay plant.
 The fact that there is such a low concentration of
phosphates is due to the large concentration of
calcium ions in the lake.
 Most of the phosphates introduced into the lake
came from municipal storm and sanitary sewers
that empty into it.
Onondaga Lake
 In 1968, Syracuse and Allied Chemical (owners of
Solvay plant) entered into an agreement where the
excess CaCl2 and Ca(OH)2 from the plant were
used to treat the city’s wastewater.
 The phosphates from the wastewater were
combined with the calcium ions to form insoluble
calcium phosphate which precipitated out before
it reached the lake.