Density classwork

```Density Classwork
Name: ____________
Part 1: Think and Explain:
In the B.P. Gulf oil spill of 2010, crude oil was released from a damaged oil well into the
saltwater in the Gulf of Mexico. The oil gushed from a broken well that was under water, yet we
were concerned for the impacts to wildlife on the water surface of the Gulf or on shore in the
Gulf states. Using what you know about density, explain why the focus for the oil was at the
surface. (Hint: think about salad dressing and the behavior of the oil and the water!)
Part 2: Density practice problems – SHOW YOUR WORK
1. A student measures the mass of a 27 cm3 block of a mysterious cube to be 108 g, what is
the density of the cube?
A.
B.
C.
0.25 cm3/g
4 g/cm3
2916 g
2. The most recent lunar mission returns with an interesting specimen. When placed in a
beaker of 200 mL of water, the water level raises to 223.5 mL If the specimen has a mass of 5.7
g, what is its density in g/mL?
A.
B.
C.
39
0.026
0.24
3. In a field study, you encounter a small shiny substance on a hillside that you think is gold!
Your teacher reminds you that there are other shiny minerals that look like gold, like pyrite
which has a density of 5g/cm3. Gold, on the other hand has a density of 19.3 g/cm3.
You find that your substance has a mass of 12.9g and it displaces 2.58 cm3 of water
Did you strike it rich?
A.
B.
Yes, my substance is gold
Nope, my substance is not the same density as gold
Part 3: Density Lab
Pick 5 materials from the collection of materials on the lab table. Fill out the chart below with
the information needed to calculate density.
Object
Mass (grams)
Volume before
(mL)
Volume after
(mL)
Volume of
object (mL)
Density
(g/mL)
20 Pre-1982
pennies
20 Post-1982
pennies
Big stopper
Small stopper
Reflection Question:
1. Explain, with evidence, why the two sets of pennies have different densities. Use physical
observations and the calculated lab densities of each set of pennies in your answer.
2. Do the two types of stoppers have the same density? Explain, with evidence, why or why not.
What does this tell you about the material that the stopper is made out of?
```