Name: Period: Score: / Water Olympics

Transcription

1 Name: Period: Score: / Water Olympics Pre-lab: With your shoulder partner research these properties or characteristics of water that make it critical for life as we know it. Include an explanation for why the property or characteristic is important. 1. cohesion: 2. adhesion: 3. capillary action: 4. polarity: 5. surface tension: 6. universal solvent: 7. high specific heat capacity: 8. density of water and ice:

2 Station 1: Pushing the Limits Make your prediction: How many pennies can you add to a full cup of water before the water spills? Directions: Fill the plastic cup with water until the water is even with the rim of the cup. Slide pennies into the cup one at a time, continuing until the water spills over. Record the number of pennies added before the water spilled. Repeat for each team member. Number of Pennies Added Describe or sketch the surface of the water. What property or properties of water did you observe at this station? Station 2: Drip, Drip, Drip Make your prediction: How many drops of water will you be able to fit on a penny? Directions: Use an eyedropper to place as many individual drops of water on the surface of a penny as possible. Continue until the water drop collapses or the water spills over the side of the penny. Record the number of drops that you could fit on the top of the penny. Repeat for each team member. Number of Drops Added Describe or sketch the surface of the water on the penny before the drop collapsed. What property or properties of water did you observe at this station?

3 Station 3: If It Floats Your Boat Make your prediction: How many paper clips can your team float on the surface of the water? Directions: Use the prongs of a fork to lay the paper clip on the surface of the water. Record the number of paper clips you could suspend in the table below. Repeat for each team member. Number of Paper Clips Added Observe the surface of the water where it meets the paper clip. Draw a picture or describe what this looks like below: Station 4: Paper towel race Make your prediction: which brand of paper towel will absorb the most water? Support your claim with two pieces of evidence: Directions: Pick up a strip of each brand of paper towel. Tape one end of each paper towel to the pencil. Lay the pencil on top of the large empty beaker so that it looks like this: pencil glass paper towel immersed in 1.5 cm water strip of paper towel water Determine how much water you will need to add to the beaker to cover the bottom 1.5cm of the paper towels. Take the pencil off the beaker and fill the beaker with that amount of water. Put the pencil back on the beaker and let the paper towels absorb the water. Once the water stops rising, measure the height that the water traveled up each paper towel using a ruler. Record your data in the chart below: Paper Towel Brand Height of Water

4 Was your hypothesis supported by your data? Station 5: Drip, drip, drip, soap Make your prediction: How will detergent affect the number of drops that can be put on the surface of a penny? Directions: Place one drop of detergent on the surface of a penny. Then add drops of water to the surface of the penny. Record the number of drops you can fit on the penny. Repeat for each team member. Number of drops of water Why did you see the results that you did? Station 6: Glass vs. Wax Make your prediction: Draw below how you think a drop of water will look on wax paper vs. a glass slide. Be sure to label your drawings. Prediction: Glass Slide Prediction: Wax Paper Now that you have your hypothesis- please place one drop of water on the glass slide and one drop of water on the wax paper. Observe and draw what happened below. Observation: Glass Slide Observation: Wax Paper Explain your results. Please remember to address whether your hypothesis was correct or not.

5 Explain the difference in water behavior in regards to adhesion between molecules of different types (ex. Glass slide vs. wax paper)? Station 7: Mix it up Pour about 5mL of liquid A into a small beaker and pour about 5mL of liquid B into another small beaker. Add an equal amount of sugar to each beaker and stir until dissolved. Continue to add equal amounts of sugar to each beaker until you cannot dissolve any more sugar. Record how much sugar you were able to dissolve in each liquid. Clean out the small beakers and leave them for the next group. Amount of Sugar Dissolved Liquid A Liquid B What do you think are the identities of the liquids? What quality do you think leads to the different liquid s abilities to dissolve sugar? Station 8: It s electric Procedure: Turn on the faucet so there is a thin but even stream of water coming out of the faucet. Take the balloon and rub it on one team member s hair for a few seconds. Slowly move the balloon close to the stream of water without touching it. Watch the water closely to see what happens. What property of water causes this effect? Draw a molecule of water below, and label each atom and the slight charges that are present on the molecule. Post Lab: On a separate sheet of paper, write a paragraph or two about the properties of water you observed in this lab. You may organize your writing around each property or each station, as long as you thoroughly discuss why the water behaved as it did at each station in terms of those properties of water. Cite specific evidence/data from each lab in your discussion.