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

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

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

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

HW #2 for 5/23

HW #2
1) HW #2 pg. 213 #51, 52

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

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.

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.

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.

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.

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 2^nd 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.

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?

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?"

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?

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.

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)

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.