1. Foundations of Physical Science Workshop: Density of Fluids

2. Density of Fluids CPO Science

3. Key Questions  Can you create a stack of liquids?  How do you find the density of a liquid?  Does the density of a liquid change as its temperature changes?

4. Overview  Calculate the Density of various fluids  Construct Density column  Use a density column to predict the density of a solid

5. What is Density?  Ratio of mass to volume-mass/vol.  Usually decreases as temperature increases  Water is a notable exception – it takes up less space in its liquid form than in its solid form; result – Ice (solid water) floats in liquid water

6. Measuring Density  Calculate mass per unit volume for each of the sample liquids  Record the density of each liquid  Rank the liquids according to density

7. Creating a Density Column  A stack of liquids  Can you make one with your sample liquids?  What order would be best when pouring them into the cylinder?

8. Using a Density Column  How can we use the stack of liquids to estimate the density of objects?  Drop objects in cylinder and observe – Make Predictions First  How can we use this information?

9. Observations  The object sinks all the way to the bottom of the stack  The object floats on top of the stack  The object is suspended somewhere in the middle of the stack, between 2 layers  How did your predictions stack up?

10. Predicting Density  The rubber stopper is suspended at the border between glycerin and water  Its density must be less than that of glycerin and greater than that of water .99 g/ml < density of the rubber stopper < 1.21 g/ml

11. Comparing Predicted and Measured Values  Stopper Mass – 4.2 g  Stopper Volume – 3.5 ml .99 g/ml < density of the rubber stopper < 1.21 g/ml  4.2 g/3.5 ml = 1.2 g/ml BINGO!