Aim: What is Density? Do Now:

1. Aim: What is Density? Do Now: In your notebooks, describe how to find the density of an object (formula). Also, what do you think determines an objects density?

2. I. Density: The amount of matter in a specific volume - A physical property of matter. - Measured in g/cm3 or g/ml. - Helps identify matter. Every object has a different density. • D = M ** Density of an object remains the same no matter how many pieces it’s broken into ** V

3. Mass Volume = Density Mass = Density x Volume Using the one density formula you can rearrange the variables to solve for mass and volume. Mass Density Density = Volume

4. M D V

5. II. Buoyancy vs. Density • Buoyancy is an objects ability to float in water. • - determines if an object will sink, float or remain neutral in water. What does neutrally buoyant look like?

6. Which color liquid is most dense? • Which color liquid is least dense? • Where would a metal sphere with a density of 3.0g/ml land? 1.3 g/ml - 2.9 g/ml - 4.3 g/ml - 5.4 g/ml -

7. Example: Compare the density of H2O (water) to the density of an ice cube. THINK An ice cube floats in H2O because it has a density: a) Equal to the density of water b) Greater than the density of water c) Less than the density of water d) None of the above

8. Why does a steel ship float in water? Densities in grams / cm3 D (water) = 1.0 g / cm3 D (wood) = 0.8 g / cm3 D (steel) = 7.8 g / cm3 D (lead) 11.3 g / cm3 D (air) .0012 g / cm3 Answer: A ship has a steel shell that is hollow inside. The volume is mostly air. The ship and air together have a density less than water.

9. Closure: From the back table, top bin; take a density review worksheet from the top bin to work on in class with your partner.