Click here to start your application for a fellowship to travel next summer for sophomores & junior (as of fall 2016). Get started during the summer and then all you need in the fall is teacher recommendations. Two of our students are attending this summer, one is traveling to Colorado and the other to Florida.
Earthwatch application
Quark
Thursday, June 2, 2016
Wednesday, June 1, 2016
HW #6 for 6/2
1)
HW
#6: pg. 354-6 #27-28, 48, 50 pg. 357 #4-5
2) Late HW #1-6 due Fri. 6/3, textbooks due 6/3
2) Late HW #1-6 due Fri. 6/3, textbooks due 6/3
Sunday, May 29, 2016
HW #5 for 5/31
1)
HW
#5: pg. 333 #3-6
2) Late HW #1-7 due Fri. 6/3, textbooks due 6/3
2) Late HW #1-7 due Fri. 6/3, textbooks due 6/3
Wednesday, May 25, 2016
HW #4 for 5/26
1)
HW
#4 pg. 694 #14-15, 25-26
2) Composition book due this Fri 5/27
3) Late HW #1-7 due Fri. 6/3
2) Composition book due this Fri 5/27
3) Late HW #1-7 due Fri. 6/3
Study Guide for Final
Spring 2016 Study Guide for Final
Topics to be covered:
·
Conservation of
Mass
·
Moles, Molar
Mass, and Molecules
·
Nuclear Processes/Radioactivity
·
Thermodynamics
and Energy
Vocabulary
Law of conservation of mass
Reactants
Products
Moles
Molar mass
Nuclear fusion vs. fission
Isotopes
Alpha decay
Beta decay
Gamma ray decay
Penetrating power
Half-life
Greenhouse gases
Climate change
Atomic number
Atomic mass
Thermal energy
Heat flow
Temperature
Exothermic
Endothermic
Specific Heat
Law of conservation of energy
Know how to do the following:
Moles and Conservation of
mass
·
Convert grams of
molecules to number of moles (and the reverse) and molecules
·
Understand what
Avogadro’s number represents
·
Molar mass of
molecules and what they represent
·
Relationship
between average atomic mass and number of moles
Nuclear Chemistry
·
Calculating how
much of sample is left in half-life questions
·
Calculating how
long a sample has been decaying for based on how much of an element has
decayed/remains
·
Identifying
missing elements in nuclear decay equations
·
Comparison of
penetrating power of each type of decay
·
Writing down
alpha and beta decay reactions of nuclear active elements
·
Problems of
fossil fuels vs. nuclear power plants
·
Pros and cons of
nuclear power plants
·
Compare fusion
vs. fission reactions for amount of energy released
Thermodynamics
·
Modeling of
molecular movements of gas, liquid and solid
·
Difference
between solid, liquid and gas in terms of energy and shape
·
Modeling of heat
flow and molecular movements depending on temperature
·
Examples of
endothermic and exothermic reactions
·
Units of specific
heat equation and each symbol
·
Calculating heat,
specific heat, grams or change in temperature using Q = s ∙m∙DT
·
Identifying
elements from the specific heat values
·
Effects of greenhouse
gases/types of greenhouse gases
Monday, May 23, 2016
HW #3 for 5/24
1)
HW
#3—pg. 678 #3b-c, 5-6, pg. 694 #12, 13b-c
2) Composition book due this Fri 5/27
2) Composition book due this Fri 5/27
Wednesday, May 18, 2016
HW #1 for 5/19
1)
HW
#1 pg. 210
#14 a-b, d, g, 15, 16
2) Bonus Lab due 5/233) Make up one take home lab #4-6 by 5/234) Math/Science night 5/19 4:30-6:30
5) Late HW #13-24 due 5/23
2) Bonus Lab due 5/233) Make up one take home lab #4-6 by 5/234) Math/Science night 5/19 4:30-6:30
5) Late HW #13-24 due 5/23
Monday, May 16, 2016
HW #24 for 5/17
Go to this website: Science World Magazine
1) Then click on the sign in button
2) Enter this password for our class: CottaS303 (make sure to use CAPITAL letters for C and S)
3) Then scroll through the issues for the magazine for December 9, 2013 with the shark eating a sea creature on the cover
4) Then click on the digital issue and look for the article in class that we read entitled "The Big Melt" on pg 14-17
5) After reading, look at page 14 for the box that says "Click for 4 bonus skills sheets" and click on it.
6) Go to the second page of the skills sheets entitled "Life on Ice" and answer those five questions on a separate sheet of paper.
1) Then click on the sign in button
2) Enter this password for our class: CottaS303 (make sure to use CAPITAL letters for C and S)
3) Then scroll through the issues for the magazine for December 9, 2013 with the shark eating a sea creature on the cover
4) Then click on the digital issue and look for the article in class that we read entitled "The Big Melt" on pg 14-17
5) After reading, look at page 14 for the box that says "Click for 4 bonus skills sheets" and click on it.
6) Go to the second page of the skills sheets entitled "Life on Ice" and answer those five questions on a separate sheet of paper.
Thursday, May 12, 2016
The Big Melt Article
Article: The Big Melt
Question: Are
there measures that we can take to reduce glaciers melting around the world?
What would be the most effective course of action?
1. Hypothesis:
We will have “glaciers” covered in nothing, plastic wrap, black construction
paper and aluminum foil that will be placed in the sun. Which glacier will melt the fastest? Slowest?
Explain your reasoning.
2. Opening
photos (pg. 14-15). Describe the photos on these pages.
3. Explain how
what you see in the photos relates to the article text.
4. Map (pg.
16). Describe the map.
5. Explain how
the map connects to information in the text.
6. Describe
the graph.
7. Explain how
the information in the graph supports the article text.
8. Which
visual element do you think best supports the central idea of the article?
Explain your answer.
Post-demonstration:
9. Which ice
cube melted the most? The least?
10. Based on
your observations, which of the materials you tested would make the best
blanket to prevent a glacier from melting?
11. What other
materials would you suggest that we test? Explain why you would want to test
these materials.
Wednesday, May 11, 2016
HW #23 for 5/12
Go to this website: Science World Magazine
1) Then click on the sign in button
2) Enter this password for our class: CottaS303 (make sure to use CAPITAL letters for C and S)
3) Then scroll through the issues for the magazine for December 9, 2013 with the shark eating a sea creature on the cover
4) Then click on the digital issue and look for the article in class that we read entitled "The Big Melt" on pg 14-17
5) After reading, look at page 14 for the box that says "Click for 4 bonus skills sheets" and click on it.
6) Go to the third page of the skills sheets entitled "Freed from the Ice" and answer those five questions on a separate sheet of paper.
1) Then click on the sign in button
2) Enter this password for our class: CottaS303 (make sure to use CAPITAL letters for C and S)
3) Then scroll through the issues for the magazine for December 9, 2013 with the shark eating a sea creature on the cover
4) Then click on the digital issue and look for the article in class that we read entitled "The Big Melt" on pg 14-17
5) After reading, look at page 14 for the box that says "Click for 4 bonus skills sheets" and click on it.
6) Go to the third page of the skills sheets entitled "Freed from the Ice" and answer those five questions on a separate sheet of paper.
Monday, May 9, 2016
HW #22 for 5/10
Visit this website:
EPA Climate Change for Students
Then complete the expeditions for these spots on the map.
1) Arctic Ocean
2) Midwest U.S.
3) Great Barrier Reef
4) Maldives
On your paper, write the answers (from questions or games) from the videos that you watch for each spot on the map. Each spot on the map has 2-3 questions. Then give the code for when you finished that spot on the map.
EPA Climate Change for Students
Then complete the expeditions for these spots on the map.
1) Arctic Ocean
2) Midwest U.S.
3) Great Barrier Reef
4) Maldives
On your paper, write the answers (from questions or games) from the videos that you watch for each spot on the map. Each spot on the map has 2-3 questions. Then give the code for when you finished that spot on the map.
Friday, May 6, 2016
Fight Club Lab
bFight Club Lab
Problem: How
is soap made? How does soap clean soiled articles? How does soap made in the
laboratory compare to commercially-prepared soap?
Introduction:
Soap is something that we regularly buy in the grocery store and use daily.
This was not always the case. Queen Isabella of Spain (1451-1504) claimed that
she had bathed twice in her entire life, once when she was born and again on
her wedding day. Queen Elizabeth I of England (1558-1603) took a bath every
three months whether she “needeth it or no”. Cleopatra, the beautiful queen of
Egypt bathed in fragrant oils. The oils softened her skin, and the perfumes
were needed to camouflage the odors produced by the bacteria on her skin. Soap
was known in ancient Rome—a soap factory was revealed among the ruins of
ancient Pompeii—but this soap was too harsh to use on skin.
The use of soap and water as we know
it began in London when people realized that poor personal hygiene was part of
the cause of cholera and typhoid epidemics. In 1846, the British government
passed a Public Baths and Wash Act. It provided public baths and laundries for
the working class of London. The idea rapidly spread throughout Europe and the
United States.
Soap is produced when a fat (or oil)
is mixed and heated with sodium hydroxide, commonly known as lye, in a chemical
process called saponification. Solid soap is the sodium salt of a fatty acid.
Soft soap is a mixture of soap and glycerol. Liquid soap is the potassium salt
of a fatty acid.
In this experiment you will synthesize
soap and then analyze its properties through several different chemical tests.
Pre-Lab
Questions:
1. What are the properties of soap that you use at home?
What functions do you expect your soap to perform? Describe what you expect
from hand soap or detergent that washes your clothes.
2. Many organic compounds are nonpolar. Will these
compounds be soluble in water? Why or why not? (remember the saying like
dissolves like)
Procedure:
1. Weigh out 15-20 g of your selected
oil or fat on a piece of weighing paper. (coconut oil, lard or vegetable shortening).
Transfer it to a 400 mL (large) beaker. Throw away the weighing paper.
2. Weigh 8 g of NaOH to a weighing dish
and place in the 250 mL (small) beaker.
Replace the weighing dish.
3. Measure 25 mL of H2O in
the larger graduated cylinder and to the NaOH and mix until completely
dissolved.
4. Add your NaOH mixture to your 400 mL
beaker that contains your fat.
5. Measure 10 mL of ethyl alcohol using
small graduated cylinder. Add this to the 250 mL beaker containing the fat and
NaOH solution.
6. Heat the mixture carefully on the
heating unit on low to medium heat, stirring it CONSTANTLY for at least 20 minutes. The solution should be HOT BUT NOT BOILING. If it looks like it will boil, take the
beaker off using the beaker tongs and turn down the heat on your hot plate.
7. After 20 minutes, carefully drip in
10 mL of additional ethyl alcohol. Stir it well. As the mixture is heated, it
will bubble and foam. Be careful to regulate your mixture by moving it as
necessary from the heat to prevent the mixture from overflowing.
8. Then after another 20 minutes, add 25
mL of water and continue heating and stirring for an additional 10 minutes.
9. After the 10 minutes, remove from the
heating unit. Allow the mixture to cool.
10. Remove the coagulated soap mass with
your spoon. Using a paper towel; shape it into a bar or a ball. You may place
it in a mold if you like to shape your soap. Place it on several layers of
paper towel and label the paper towel with your group members name. Observe and
record its smell and appearance.
11. Allow the soap to air dry until the
next laboratory session.
Procedure:
Part 2 Testing the Soap
1.
Place 10 mL of water in each of the three test tubes. Add 0.5 g of your
soap to your first test tube. Stopper the tube and shake vigorously to test the
foaming action of your soap. Repeat this process using commercial soap in the
second test tube and commercial detergent in the third test tube. Use 0.5 g of
soap each test. Record your observations. Put your test tube to the side and
arrange them in order to not mix them up.
2.
Add 2-3 drops of phenolphthalein indicator solution to your first
prepared test tube. Shake and record your observations. Repeat this process
using commercial soap in the second test tube and commercial detergent in the
third test tube. Record your observations. Clean out the test tubes. (Reminder:
phenolphthalein turns dark pink in strong base and light pink in weak base. It
is clear in neutral and acidic solutions.) Clean out the test tubes at the sink
with a test tube brush.
3. Place 10 mL of water in each of the
three test tubes. Add 8-10 drops of vegetable oil to each tube. Note that the
oil forms a separate layer on top of the water. Stopper and shake the first
tube. Add a 0.5 g of your soap to the first test tube. Stopper the tube and
shake till all the soap is dissolved. Allow the tube to stand a few minutes and
move on to prepare a 2nd test tube.
Repeat this process using commercial soap in the second test tube and
commercial detergent in the third test tube. After allowing the test tubes to
sit, observe how much oil remains in each of the test tubes. Record your
observations. Clean out the test tubes.
4. Place 10 mL of water in each of the
three test tubes. Add a 0.5 g of your soap to the first test tube. Stopper the
tube and shake to dissolve the soap. Add 10-12 drops of CaCl2 solution
to the soap solution. Shake and record the results. Repeat this process using
commercial soap in the second test tube and commercial detergent in the third
test tube. Record your observations. Clean out the test tubes.
Data:
|
Test Tube #1:
Your soap
|
Test tube #2:
Commercial soap
|
Test tube #3:
Commercial detergent
|
Color, texture and appearance of the
soap:
|
|
|
|
Sudsing test:
|
|
|
|
Phenolphthalein test
|
|
|
|
Oil test:
|
|
|
|
Calcium chloride test:
|
|
|
|
Analysis:
1. How do the sudsing actions of the
soaps (both yours and commercial soap) and detergent compare?
2. How do the oil breakup capabilities
of the soaps and detergent compare?
3. Calcium chloride releases calcium
ions in the water. This makes the water “hard”. How do the results of the soaps
and detergent compare in hard water?
4. How do the pH values of the
commercial soap and detergent compare with your soap?
5. In the lab used fats and oils to make
your soap and they are organic compounds.
What are some of the properties of organic compounds that you can
hypothesize from working with the fat. (Hint: think about the properties we
have studied about elements such as boiling point, density.)
6. How did your soap compare to the soap
from the store? Do you think it as good at those you purchase? Explain why or
why not.
HW #21 for 5/9
Visit this website about climate change and answer the following questions:
http://climatekids.nasa.gov/menu/big-questions/
Go to the section: " What can we do to help?"
1. What are the three things that you can do when you get older? Which would you be most willing to do?
2. What are three things you can do to reduce your "carbon footprint"? Which one you be willing to do right now to help out?
3. Name three ways to reduce your trash contribution. What is the easiest one to do?
4. Take the carbon footprint calculator on this website: carbon footprint calculator.
5. Then tell how many tonnes of CO2 are released from your activities and how many Earths we would need if every lived like you.
http://climatekids.nasa.gov/menu/big-questions/
Go to the section: " What can we do to help?"
1. What are the three things that you can do when you get older? Which would you be most willing to do?
2. What are three things you can do to reduce your "carbon footprint"? Which one you be willing to do right now to help out?
3. Name three ways to reduce your trash contribution. What is the easiest one to do?
4. Take the carbon footprint calculator on this website: carbon footprint calculator.
5. Then tell how many tonnes of CO2 are released from your activities and how many Earths we would need if every lived like you.
Thursday, May 5, 2016
Bonus Take Home Lab #2
Take Home Lab Bonus #2: Penny Sandwiches
Question: From 1864 until 1983, the
usual composition of a penny (its actual name is “cent”) was 95% copper and 5%
zinc and tin. Because of the increasing costs of copper, pennies are now
composed of a zinc interior with a thin copper coating comprising only 2.4% of
the penny. This activity allows you to remove the inside of the penny, leaving
only the thin copper coating.
Safety: Do not seal the bottles. The
pressure of the hydrogen gas may be sufficient to shatter the bottles.
Materials: 2 pennies (dated 1983 or
later), a file or coarse sandpaper, 2 cups lemon juice, 2 cups vinegar, 2 clear
wide-mouthed containers (greater than 2 cup measurement)
Procedure:
STEP 1:
Using the file or coarse sandpaper, completely remove the copper coating
from the edge of both pennies. Pour the lemon juice into one container.
Position one penny in the container so that it is standing on its edge against
the side of the container. Pour the vinegar into the second container and
similarly position the second penny. Observe the pennies for 4 or 5 minutes.
What do you see? What is occurring? What is the identity of the observed
substance?
STEP 2: Observe the pennies over the
course of 1 week and describe any difference(s) in their behavior. What
accounts for the difference(s)? What specific process is occurring in each
container? How do you know when the processes are complete? Use your
observations to rank the three elements hydrogen, copper, and zinc from most to
least reactive.
Observations:
Step 1:
Penny in container of lemon juice—
Penny in container of vinegar—
Step 2: Penny in lemon juice after 1 week—
Penny in vinegar after 1 week—
Post-Lab Questions:
1. What gas do you think is being
released by the pennies?
2. Was there a difference between the container
of vinegar and lemon juice? Why do you think there was a difference if there
was one?
3. Rank
these from the most to the least reactive. Copper, zinc and hydrogen.
4. What do you think is more reactive
lemon juice or vinegar? Explain from your observations.
5. Why do you think they place a copper
coating on the penny?
Bonus Take Home Lab #1
Take Home Lab Bonus #1: Tissue in a Cup: How Soggy?
Question: Have you washed any cups or
glasses recently? Have you ever tried to submerge an inverted glass, jar, or
cup into water only to have it bob back to the surface without the inside
getting wet? What does this have to do with chemistry? You will find out as you
investigate several aspects of this phenomenon through this activity.
Safety: Clean up any spills
immediately, be careful of push pin and nail
Materials: clear glass or plastic cup,
paper cup, tissues or paper towels, push pin or nail, ice cold water, very hot
tap water, 2 containers to completely submerge the cups (preferably clear)
Procedure:
STEP 1:
Fill one large container with ice-cold water. Fill the second large
container with very hot tap water. Submerge an inverted clear cup or glass in
the cold water for several minutes and observe from the side. Remove the cup
from the cold water and, taking care not to burn yourself, submerge the
inverted cup in the hot water for several minutes and observe as before. Repeat
the submersion in cold and then hot water. Record your observations. Explain
any differences in your observations of the cup in cold and hot water. Draw a
picture to show the difference between the hot and cold water.
STEP 2: Using any of the materials
listed above, devise a way to submerge a tissue or paper towel under water
without getting it wet. Briefly outline your procedure and draw a labeled
picture to illustrate what you observed. What kept your tissue from becoming wet?
STEP 3: Using any of the materials
listed above, devise a way to submerge a tissue or paper towel under water
without getting it wet. Briefly outline your procedure and draw a labeled
picture to illustrate what you observed. What kept your tissue from becoming
wet?
Observations:
Step 1: Cold water container—
Hot water container—
Step 2: Tissue in the cup—
Step 3: Paper cup with hole--
Diagrams w/ labels explaining the parts:
Step 1:
Step 2:
Step 3:
Post-Lab Questions:
1. What happened to the air in the
submerged cups?
2. How was the hot water result
different from the cold water? Why do you think this is?
3. Did
your tissue paper get wet? Why or why not?
4. What did you do right, what did you
do wrong?
Tuesday, May 3, 2016
HW #20
Visit this website about climate change and answer the following questions:
http://climatekids.nasa.gov/menu/big-questions/
Go to the section entitled: "What is the big deal with carbon?"
1. Explain how carbon, the element, is different than when it is in a compound with other elements.
2. Explain how oil and natural gas are formed in our Earth.
3. Explain what is good and what is bad about the greenhouse effect.
Go to the section entitled: "What is happening in the ocean?"
http://climatekids.nasa.gov/menu/big-questions/
Go to the section entitled: "What is the big deal with carbon?"
1. Explain how carbon, the element, is different than when it is in a compound with other elements.
2. Explain how oil and natural gas are formed in our Earth.
3. Explain what is good and what is bad about the greenhouse effect.
Go to the section entitled: "What is happening in the ocean?"
4. Explain how relationship between algae and coral is beneficial to each species.
5. How are ocean animals that have shells and corals affected by the changing ocean.
6, What is more dense: hot or cold ocean water? What effect does salt have on density?
Monday, May 2, 2016
Ice/Water/Steam Investigation Lab
Ice/Water/Steam Investigation Lab
Question: What
happens to the temperature of the water molecules as it changes state from
solid to liquid and then to gas. How
does salt effect the boiling temperature of the water?
Objective: To observe the temperature and heat of H20 as it changes state. You will create your own procedure and use any materials listed. Then after you observe your water boil, add salt to the water and observe its temperature.
Materials you can use: Hot plate, thermometer, balance, cups, beaker, stirrer,
graduated cylinder, stopwatch on your phone, salt
RULES:
1. DO NOT LEAVE THE THERMOMETER IN THE BEAKER. Do NOT let it sit at the bottom of the beaker, hold it in the middle.
1. DO NOT LEAVE THE THERMOMETER IN THE BEAKER. Do NOT let it sit at the bottom of the beaker, hold it in the middle.
2. The amount of salt you use it up
to but write down the total.
3. Stir your ice/water mixture
regularly.
4. Your hot plate must be on a low
setting, not turned all the way up.
5. Do NOT place anything on the hot
plate except the beaker.
In your composition book:
1. Provide a
detailed list of your steps in your procedure. Make sure to detail how much
ice, salt and water you have in your experiment.
2. Collect
data in a data table and make sure it is legible and it is clear what you are
collecting and units are used.
3. Create a line
graph of your data showing change over time.
4. Write an
explanation of what your data showed during your investigation as it relates to
the ice, temperature and heat. (Hint:
Think about including words such as melting, boiling, heat, temperature,
constant.)
5. According
to your data and graph, what is the freezing temperature of water? The boiling
temperature?
6. Look at the
graph. Did you have a period of time where your temperature was constant?
Explain when and what was happening in your experiment.
7. What effect
did adding salt have to water when it was boiling? How is this related to your
ice cream lab?
8. Create a
model the ice before you added heated and then when it completely melted, then
when it was boiling. (Three models in total)
Sunday, May 1, 2016
Take Home Lab #6
Take Home Lab #6: Measure a Meltdown
Question: What will happen to the
Earth’s oceans if the ice melts in places such as Antarctica and Greenland?
Does melting icebergs cause sea level change?
Safety: Clean up any spills
immediately.
Materials: clear glass or clear plastic
bowl about 6 in/15 cm in diameter, ice cubes, warm water, pencil/marker, ruler
Procedure:
Trial #1:
1. Pour warm
water so that the level of the liquid is roughly 2.5 centimeters (1 inch) from
the top of the bowl.
2. Place 4-5
ice cubes in the bowl.
3. Use a
water-based marker (one that will wipe off easily!) to draw a line on the
outside of the container at the level of the water after you placed the ice
cubes.
4. Set the
bowl aside for 15 minutes, or until all of the ice melts.
5. Mark the
new level of the water. Then use a ruler to measure how much the level changed.
Trial #2:
1. Think about whether your experiment in Trial
#1 represents melting icebergs (ice that is already floating in the sea) or
glaciers (huge ice sheets on land such as Antarctica and Greenland).
2. How could
you modify your experiment so that it models how melting glaciers would affect
sea level.
3. Repeat
your experiment with your new set up.
Data Table:
|
Initial height:
(Describe the height of your ice cubes and water before_
|
Final height:
(Describe the height of your ice cubes and water after)
|
Trial #1: ice cubes in water
|
|
|
Trial #2: your design
|
|
|
Post-Lab Questions:
1. Explain does Trial #1 represent
melting icebergs or melting glaciers? Explain which it shows and why.
2. Explain how you conducted your
experiment in Trial #2. Explain your set up.
3. Did the water levels in your trails
rise or fall when the ice melted? Explain how Trial #1 was different or the
same from Trial #2.
4. In which setup did the water level
change the most? By how much?
5. Which melting ice will have the
largest impact on sea levels: icebergs or glaciers? Support your answer with
evidence from your experiment.
Friday, April 29, 2016
HW #19 for 5/2
Answer on a piece of separate piece of paper:
Identify each of the following changes as chemical or physical. If it is a physical change give the name of the change of state. Then identify if it is an exothermic or endothermic reaction. :
1.) Solid iodine turns directly into gaseous iodine when left on your table.
2.) Solid sodium hydroxide mixes with liquid water and the mixture turns very hot.
3.) A cold pack is activated by a packet of liquid water is burst open and mixed with solid ammonium nitrate and immediately turns cold.
4.) Outside a bottle of water is left out and turns to gaseous water.
5.) Then overnight, the weather turns cold and the gaseous water forms frost on the plants outside.
6.) A cake is mixed and cooked in the oven for Mother's Day.
7.) Special sun paper is left outside in the sun and it turns to a different color.
8.) Steam collects underneath the lid of a pot and turns to water drops.
Identify each of the following changes as chemical or physical. If it is a physical change give the name of the change of state. Then identify if it is an exothermic or endothermic reaction. :
1.) Solid iodine turns directly into gaseous iodine when left on your table.
2.) Solid sodium hydroxide mixes with liquid water and the mixture turns very hot.
3.) A cold pack is activated by a packet of liquid water is burst open and mixed with solid ammonium nitrate and immediately turns cold.
4.) Outside a bottle of water is left out and turns to gaseous water.
5.) Then overnight, the weather turns cold and the gaseous water forms frost on the plants outside.
6.) A cake is mixed and cooked in the oven for Mother's Day.
7.) Special sun paper is left outside in the sun and it turns to a different color.
8.) Steam collects underneath the lid of a pot and turns to water drops.
Ice Cream Lab
ICE CREAM LAB
Problem: When you make ice cream what is the purpose of the salt
that is added to your ice? You will experiment different ratios with and
without salt to see which is the most successful.
Pre-Lab Questions:
1. What do you think would make a “successful” ice cream in lab?
What would you like your ice cream to be like before you eat it?
2. Is making ice cream a physical or chemical change? Explain why.
3. What is the change of state that is occurring when you make ice
cream? Is it exothermic or endothermic? Explain why.
Make your hypothesis:
What ratio of salt to ice do
you think will produce ice cream the fastest, and give the reason why you think
this.
Procedure:
1. Place 6 cups of ice in your
milk jug.
2. Measure your salt on the
scale as listed in your assigned ratio below.
3. Place your salt with your
ice and shake up your jug to mix it up.
4. Take your tin can to Ms.
Cotta to fill with the ice cream solution.
Ratio Amounts
0:100 no salt, 6 cups of ice
1:10 40 g salt, 6 cups of ice
1:8 50 g salt, 6 cups of ice
1:5 80 g salt, 6 cups of ice
1:4 100 g salt, 6 cups of ice
1:2 200 g salt, 6 cups of ice
1:1 400 g salt, 6 cups of ice
5. Push your tin can down into
your ice and salt mixture so that it is surrounded by ice cream on the sides
and underneath.
6. Put your thermometer into
the ice (NOT THE ICE CREAM) and measure the initial temperature of the ice.
7. Stir your ice cream
regularly with the wooden stick so that it will freeze evenly. The bottom and
sides will freeze first.
8. Every five minutes check the
temperature of the ice and write it in your data table.
9. Check the consistency of the
ice cream and write and observation such as runny (still like milk), thin
(little frozen pieces), thick (almost frozen).
10. After 30 minutes you may
dish out your ice cream to you and your partner and try it out.
Data Table
Salt to Ice Ratio
(write your ratio)
|
0
mins
|
5
mins
|
10
mins
|
15
mins
|
20
mins
|
25
mins
|
30
mins
|
Temperature
|
|
|
|
|
|
|
|
observation (runny, thin,
thick)
|
|
|
|
|
|
|
|
Clean-Up:
1. Wash out your tin can and
replace at your table.
2. Wash out your milk jug in
the sink and replace at your table.
3. Wash out your bowls (IF THEY
ARE PLASTIC) and recycle them in blue bin.
4. Throw out your spoons and
wooden stick.
5. Wipe down your table with a
sponge if needed.
Conclusion:
Use the following words to
explain this experiment to someone else in a short paragraph: freezing, melting, temperature, ice cream,
mixture. Please underline
each of these words in your paragraph.
Questions:
1. Why did the ice cream solution freeze? What is required to turn
your liquid to a solid?
2. Which ratio makes ice cream the fastest? What is your evidence
for this?
3. What is the purpose of the salt? Would this work without salt?
What is your evidence?
4. What was the change of state that occurred? Is it a physical or
chemical change? Why?
5. What is the variable (the thing that changes) and controls (the
things that stay the same) in this experiment?
6. Draw a model showing what your ice cream mixture was like when
it was first place in the ice and then a second model showing it at the end of
30 minutes. Show the speed of the molecules and explain which way the heat is
flowing.
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