Activity 5: Density

1. Run the Build an Atom simulation http://phet.colorado.edu/en/simulation/build-an-atom and build a neutral lithium atom and a neutral boron atom.  Take a picture, or a screen shot, of these two atoms and place them on your blog.  List the number of protons, neutrons and electrons for each. Also look up and post the density for each of the elements on your blog.

Protons - 3, Neutrons - 4, Electrons - 3, Density -  0.53 g.cm ^-3 at 20 °C

Protons - 5, Neutrons - 5, Electrons -5, Density  -  2.3 g.cm^-3 at 20°C

2. Define density and the equation for density and post on your blog.
Density can be defined as mass or weight per unit of volume, the equation to find density is:

ρ is the density, m is the mass, and V is the volume 

3. Run the Density simulation http://phet.colorado.edu/en/simulation/density and complete one(your choice) of the prepared Teaching Ideas and post your results on your blog. The activity you choose should be one of the student intended activities.

PhET- Density Activity- Funsheet

Custom Section                                                                                                          Name_____________

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
Styrofoam	59	100.59	1	Yes
Wood	1.59	101.59	1	Yes
Ice	3.64	103.64	1	Yes
Brick	7.93	103.97	1.99	No
Aluminum	10.71	103.97	2.69	No

1.     In the custom setting, choose the ‘My Object’ option in the material drop down box.  Set the mass of your object to 4 kg.  Adjust the volume to find the minimum volume needed to make the object float.

Volume______4.01_____                Density______.9975_

2.     How does the density of a large piece of aluminum compare to a small piece?

1 kg – 100.37                2.702702702702703  

10 kg – 103.70              2.702702702702703

They are exactly the same, because they are already both completely emerged in water because of their density the volume can't go up any higher.

Same Mass Section

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
Blue	5	105.00	1	No
Yellow	5	105.00	1	Yes
Green	5	102.50	2	No
Red	5	101.25	4	No

Same Volume Section

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
Blue	6	105.00	1.2	No
Yellow	8	105.00	1.6	No
Green	4	104.00	1	Yes
Red	2	102.00	1	Yes

Same Density Section:

3.  Calculate the density of the blue object in this section.

     Mass ____3.00______         Volume______103.75_________        Density______0.2133_______

4.  Explain why both the yellow and red objects float when they have different sizes.

Mystery Section:

5.  Before you start, pick an object that you think will float.  _____Blue B____________

     Pick an object that you think will sink.  ______Purple E______________

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
A	65.14	103.38	0.6301025343393306	No
B	.64	100.64	0.0063593004769475	Yes
C	4.08	104.08	0.0392006149116065	Yes
D	3.10	103.10	0.0300678952473327	Yes
E	3.52	101.00	0.0348514851485149	No

6.  In the Custom section describe the difference between how Styrofoam and ice  

     floated.  Also explain why you think this is the case?

The Styrofoam floated mostly above the water, because its material is much less sense than water, while the Ice floated mostly below the water level because Ice is water, but in a more dense form.

7.  In the Mystery Section, click on the “Show Table” button.  What is the most dense   

     object on the list?  Write its density as well.

Lead, 19.3 is leads density.

8.  List something you learned from this activity.
I learned that with objects looks are not always correct, just because an object is tiny does not mean it will float and be light, whereas just because an object is large does not mean it will be heavy and sink.

4. Complete the Mystery Blocks activity on the Density simulation.  Post on your blog the data you collected (mass, volume, and density) and the identification of the material and the known density.

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?	Object and known mass
A	65.14	103.38	19.28	No	Gold 19.3
B	.64	100.64	1	Yes	Water 1
C	4.08	104.08	1	Yes	Water 1
D	3.10	103.10	1	Yes	Water 1
E	3.52	101.00	3.52	No	Diamond 3.53

5. Identify and post on your blog the Science Standards that could be met through these activities completed in Activity 5
A.4.3 When investigating a science-related problem, decide what data can be collected to determine the most useful explanations
C.4.2 Use the science content being learned to ask questions, plan investigations, make observations, make predictions, and offer explanations
D.4.5 Construct simple models of what is happening to materials and substances undergoing change, using simple instruments or tools to aid observations and collect data