Activity 5

To complete Activity 5, complete the tasks below:
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: 3

Electrons: 3

Density: .534g/c³

Protons: 5

Neutrons: 5

Electrons: 5

Density: 2.34 g/c³

2. Define density and the equation for density and post on your blog.
Density is the mass of a substance per unit of volume
Equation: mass/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	.75	5.00	.15	yes
Wood	2.00	5.00	.40	yes
Ice	4.60	5.00	.92	yes
Brick	10.00	5.00	2.00	no
Aluminum	13.50	5.00	2.70	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_______4.08 L__________                Density_______.98kg/L___________

 

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

 The density will stay the same, no matter the size.

 

 

Same Mass Section

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
Blue	5.00	5.00	1.00	no
Yellow	5.00	5.00	1.00	yes
Green	5.00	2.50	2.00	no
Red	5.00	1.25	4.00	no

 

Same Volume Section

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
Blue	6.00	5.00	1.20	no
Yellow	8.00	5.00	1.60	no
Green	4.00	4.00	1.00	yes
Red	2.00	2.00	1.00	yes

3.  Looking at the data on the previous page, what must be true about the density of

     an object in order for it to float?

 The density has to be 1.00 kg/L or less for an object to float.

 

Same Density Section:

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

 

     Mass ____3.00 kg_________         Volume______3.00 L_________        Density_____1.00 kg/L___________

 

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

 

They have the same density.

 

 

 

Mystery Section:

6.  Before you start, pick an object that you think will float.  _________B__________________

     Pick an object that you think will sink.  ____________C_____________

 

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
A	65.14	3.38	19.27	no
B	.64	,64	1	yes
C	4.08	4.08	1	yes
D	3.10	3.10	1	yes
E	3.53	1.00	3.53	no

 

 

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

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

 Styrofoam floated way up by the top while the ice floated barely above the water level. I think this is because the ice is more dense than the Styrofoam.

 

 

8.  In the Same Mass Section discuss what was interesting about the blue object’s behavior in the water.

 The blue object should have floated because it has a density of 1.00 kg/L but it sank.

 

 

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

     object on the list?  Write its density as well.

 

Gold: 19.3 kg/L

 

 

10.  List something you learned from this activity.

I learned that density is mass/volume.

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)	ID and known density
A	65.14	3.38	19.27	Gold 19.3
B	.64	.64	1	Water 1.00
C	4.08	4.08	1	Water 1.00
D	3.10	3.10	1	Water 1.00
E	3.53	1.00	3.53	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
C.4.5 Use data they have collected to develop explanations and answer questions generated by investigations