1. Wednesday, August 19th Who Sank the Boat?

2.  Please take out your lab book  Pencil  Calculator  Warm Up:  Discuss with your table the steps needed to determine the density of a regular shaped object (example: a block of wax) and write them in their lab books – PAGE 33

3. Sink or Float?  Learning Goal: Students will understand how to calculate density of an object and compare it to the density of water.  Objective: Students will be able to calculate the density of blocks and irregular objects and predict if they will float in water.  Materials:  Blocks – Various Sizes!  Triple beam balance  Metric Ruler  Calculator

4. Sink or Float Density Lab Pre-Lab Questions – Lab Book P. 33 1.Do you think any of the blocks have the same density? 2.What evidence do you have to support your answer? 3.What measurements will you need to make to test your hypothesis? 4.Devise a hypothesis predicting if each block will sink or float in water. (What is your independent variable? What is your dependent variable?)

5. Procedures 1.Work with a partner within your group to determine the density of each of the blocks. 2.You will need to share the blocks with the other members of your group.

6. 3.Record your calculations on the data table in your lab book, page 33. The data table should include the following: 4.Check your results and calculations against those of the other pair in your group Type of BlockMass (g) Volume (cm3) Density (g/cm3)Sink/Float

7. Before the Big Event Questions! – Answer the following in complete sentences (except question #4) on p. 32 in your lab book. 1.Are the densities of the different blocks the same or different? 2.How could this information be used to identify what the block is made of? 3.Review the hypothesis made at the beginning of the activity. Based on your density calculations, do you want to change any of your predictions? Why? 4.Next to each block on the data table, write your prediction. Will the block sink or float in water.

8. Conclusion Questions – Answer the following in complete sentences ON A SEPARATE SHEET OF PAPER 1.What is the difference between mass and volume? 2.What units are used to measure mass and volume? 3.How is the density of an object calculated? 4.What units were used to measure density? 5.If two objects are made from the same substance, will they have the same density? 6.Were your predictions for each object correct in the sink or float column? Write a short paragraph describing which were correct or incorrect and why did each item sink or float in the water.