Standards: E. 2 – Understand the history of Earth and its life forms based on evidence of change recorded in fossil records and landforms

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  1 Quart size Zip loc baggy
  
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  Plastic pipette filled with water
  
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  Sodium Bicarbonate (Baking soda)
  
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  Calcium Chloride (Damp rid)
  
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  2 Aluminum tins
  
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  Balance
  
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  Plastic spoons
  
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  Paper towels
  
• 
  Thermometer
  

1. 
   Record predictions of observable changes after adding chemicals and water.
   
2. 
   Add 2-3 t of baking soda and damp rid into bottom of the baggy.
   
3. 
   Mix well and shake to one side of baggy.
   
4. 
   Measure and record the total mass of the baggy, baking soda and dam rid.
   
5. 
   Add thermometer to baggy. Record the initial temperature.
   
6. 
   Measure mass of pipette filled with water.
   
7. 
   Carefully place pipette into baggy without spilling any water
   
8. 
   Remove air from baggy and seal baggy completely.
   
9. 
   Slowly squeeze water into dry mixture and mix well. Record the final temperature.
   

• 
  Baking soda + water cooler (endothermic)
  
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  Damp rid + water  warmer (exothermic)
  
• 
  Add 2 parts damp rid and 1 part baking soda to water.
  
• 
  Add 2 parts baking soda and 1 part damp rid to water.
  

• 
  Students illustrate physical changes, thermal energy transfer, states of matter, solubility and solutions.
  

Label your diagram using at least 5 terms from the word wall.

(Example: Thermal energy, Solubility, Molecule, Solid, Liquid, Gas, Solution, Mixture, etc…)

Group: Create a mind map illustrating relationship between energy and physical changes

Density Column

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  Students observe differences in physical properties: Density, viscosity, etc…
  

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  Prior to this lab, students can conduct the Float or Sink investigation from the AIMS Chemistry book.
  

• 
  30-50 ml of each liquid listed below
  
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  7 Pipettes or plastic spoons
  
• 
  1 Large graduated cylinder
  

1. 
   Add food coloring to 5 of the liquids (as indicated below)
   
2. 
   Based on density, ask students to predict the order of layers after all liquids are added
   
3. 
   Into large graduated cylinder, use a pipette or pour over the back of a spoon, to slowly add 30-50 ml of each of the following in order
   

2 Light Karo Syrup (green)

3 Dawn dish soap (blue)

4 Water (purple)

5 Vegetable Oil

6 Rubbing Alcohol (red)

7 Lamp Oil (orange)

Follow up: Compare predictions with observations

• 
  Ask students to predict where the objects from Float or Sink would be in the column.
  

• 
  Students can create a smaller version of the density column in clear plastic straws by covering the bottom with clay or tape and adding a few drops of each liquid using eye droppers.
  

• 
  Odorless Paint Thinner
  
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  Oil paint in tubes
  
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  3 Solvent cups
  
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  3 Eyedroppers
  
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  1 Aluminum Pan
  
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  5 Toothpicks
  
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  3-5 Sheets of paper (5’ x 8’) per student
  
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  3 Paper towels per student
  
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  Pencil
  

Prior to lab:

1. 
   Add ½ in. of each paint color to solvent cups.
   
2. 
   Add 2-3 T paint thinner to each solvent cup
   
3. 
   Replace solvent cup lid and mix well.
   
4. 
   Into aluminum pan, add 1-2” of water.
   
5. 
   Use eyedropper to drop 3-4 drops of paint onto surface of water.
   
6. 
   Use toothpick to swirl paints.
   
7. 
   Write name on bottom of each sheet of paper in pencil.
   
8. 
   Drop paper onto surface of water.
   
9. 
   Pick up paper from one end allow excess water drain off, back into pan.
   
10. 
    Place paper on paper towel to dry.
    
11. 
    Use a sheet of paper to clean top of water surface between students.
    

http://pbskids.org/fetch//parentsteachers/activities/act/act-floatmyboat.html

Drops On a Penny (this is also in the AIMS Chemistry Book)

http://www.stevespanglerscience.com/lab/experiments/penny-drops

EXPERIMENT

1. 
   Wash and rinse a penny in tap water. Dry it completely with a paper towel.
   
2. 
   Place the penny on a flat surface. The flatter the surface is, the better this experiment is going to go.
   
3. 
   Use an eyedropper or pipette to draw water and, carefully, drop individual drops of water onto the flat surface of the penny.
   
4. 
   Keep track of the water drops as you add them, one at a time, until water runs over the edge of the penny. You’ll probably be surprised by the number of drops you get on there.
   
5. 
   Repeat the experiment as many times as you want, or take it further by testing another liquid like vegetable oil, salt water... whatever you want! Use a table similar to the one below to keep track of your trials and liquids.
   

Data Table:

There are two properties at work in this experiment: cohesion and surface tension. Cohesion is the attraction of like molecules to one another. In this case, the like molecules are the H20 molecules in the water drops. Surface tension is a special term we use to describe the cohesion between water molecules.

Water’s cohesion and surface tension are special because of hydrogen bonds. Hydrogen bonds are formed by the hydrogen atoms of one molecule being attracted to the oxygen atoms of another molecule.

The cohesion and surface tension of water becomes apparent when the drops of water you add to the penny reach the penny’s edge. Once the water has reached the edge, you begin to see a bubble or dome of water forming on top of the penny. The bubble shape is a result of the water molecules clinging to one another in an optimal shape (just like the bonds on the surface of a blown bubble).