Activity #5

#1. Lithium: 3 protons
                   3 neutrons
                   3 electrons
     Density:  0.534 grams per cubic centimeter
Boron:        5 protons
                  5 neutrons
                  5 neutrons
      Density: 2.37 grams per cubic centimeter
 Boron
  Lithium

2. The degree of compactness of a substance is density- density= mass/volume
3 and 4.  Guide for Density Simulation:                               Name: _Molly Brion________________

(note: “sink” means stays on the bottom)

Google:   Phet Density sim

Start:    1.                                                 

              2.           Click on the first link

     3.           Click on the   button

     4.          Experiment with choosing a material:

material	S=sinker F=Floater	Density given
Styrofoam	F	.89 kg
Wood	F	2.62 kg
Brick	S	6.01 kg
Ice	F	13.08 kg
Aluminum	S	17.66 kg

Put the materials in the correct boxes

5.    Try to get aluminum to float.      Talk with your partner about this possibility- can you change the mass of the aluminum block without changing the volume of the aluminum block?  No, the aluminum block will not float.

6.    What do you and your partner notice about the density triangle at the bottom of the box?  Why do you think this does or does not move? It stays the same because the density of aluminum is the same and it doesn’t change.

                                            

7.                          How does the density of aluminum (2.70 kg/L)  help explain what you see?

_No matter what you end up changing the density will end up being 2.70 kg/l after you divide the mass by volume.

Frame:  The aluminum will __sink_____________ in the water because the density of the aluminum is _2.70______kg/L and the density of water is ___1.00______kg/L_.  We have learned that _the mass and volume can change but the density will not.______

8.    Density  = ----------       “_mass______ over _volume_____ equals ___density____________”

In the “Blocks” box, click on Mystery:

Test the boxes in the water- just drag and drop!!!

   

When you have determined which ones sink and float, fill in the data table for each box. 

Sample	Starting volume of water (A)	volume of water and block (B)	Volume of block alone (difference B-A)	Mass (kg)	Density (kg/L)	What is it most likely made of? (hint: use Show Table for help)
A	100-L	103.38 L	3.38 L	65.14 kg	19.22 kg/L	Gold
B	100-L	100.64 L	.64 L	0.64 kg	1 kg/L	water
C	100-L	104.08 L	4.08 L	4.08 kg	1 kg/L	water
D	100-L	103.10 L	3.10 L	3.10 kg	1 kg/L	water
E	100-L	101.00 L	1.00 L	3.53 kg	3.53 kg/L	diamond

9. 
 Look closely at green box C and red box D and discuss your observations.

 List three observations you made while comparing the two boxes.

1st observation C floats higher

2nd observation C is a larger object

3rd observation C weighs more

10. Dear Students,

I am going to build a boat.  My partner says I cannot put a refrigerator and a television in my boat because that would make it too heavy-and the boat might sink. Then we would be swimming with the sharks!!!!

What would you advise me to tell my friend? Is she right or wrong?  Be sure to give me some evidence based on what you learned from the boxes or other places in this activity.

___Make you’re your boat is big enough to hold up the weight of the refrigerator and t.v.  

…you can write on the back if you need more room to write!       Signed, your teacher

5. A.4.3 When investigating a science-related problem, decide what data can be collected to determine the most useful explanations

A.4.4 When studying science-related problems, decide which of the science themes are important

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

C.4.6 Communicate the results of their investigations in ways their audiences will understand by using charts, graphs, drawings, written descriptions, and various other means, to display their answers

D.4.1 Understand that objects are made of more than one substance, by observing, describing and measuring the properties of earth materials, including properties of size, weight, shape, color, temperature, and the ability to react with other substances