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.

Lithium

Density of Lithium= 0.534 kg/L

# of Protons: 5

# of Neutrons: 0

# of Electrons: 3

Boron
Density of Boron=2.34 kg/L

# of Protons: 7

# of Neutrons: 0

# of Electrons: 5

2. Define density and the equation for density and post on your blog.
ANSWER:
The definition of DENSITY is the degree of compactness of a substance.

The equation used to determine density is:

(Density=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.

For my chosen activity, I completed the fun sheet for Density Buoyancy by Milton Johnson. The following information comes from the lesson Mr. Johnson provided on the website.

PhET- Density Activity- Funsheet

Custom Section                                                                                    

Name Zahida Severson

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
Styrofoam	0.75 kg	5 L	0.15 kg/L	yes
Wood	2.00 kg	5 L	0.4 kg/L	yes
Ice	4.6 kg	5 L	0.92 kg/L	yes
Brick	10 kg	5 L	2.0 kg/L	No
Aluminum	13.5 kg	5 L	2.7 kg/L	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 L________                Density_____1 kg/L________

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

ANSWER: The density would be the same.

Same Mass Section

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
Blue	5 kg	5 L	1 kg/L	Yes
Yellow	5 kg	10 L	0.5 kg/L	Yes
Green	5 kg	2.5 L	2 kg/L	No
Red	5 kg	1.25 L	4 kg/L	No

Same Volume Section

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
Blue	6 kg	5 L	1.2 kg/L	No
Yellow	8 kg	5 L	1.6 kg/L	No
Green	4 kg	5 L	0.8 kg/L	Yes
Red	2 kg	5 L	0.4 kg/L	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?

            ANSWER: The density of an object must be 1 or lower in order for it to float.       

Same Density Section:

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

     Mass ___3 kg___        Volume____3.75 kg___       Density___0.8 kg/L___

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

            ANSWER: The yellow and red objects are able to float because they both have a density that is less than 1 kg/L.

Mystery Section:

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

     Pick an object that you think will sink.  _________E______________

Material	Mass (kg)	Volume (L)	Density (kg/L)	Does it Float?
A	65.14 kg	3.38 L	19.27 kg/L	No
B	0.64 kg	1 L	0.64 kg/L	Yes
C	4.08 kg	5.83 L	0.7 kg/L	Yes
D	3.1 kg	3.38 L	0.92 kg/L	Yes
E	3.53 kg	1 L	3.53 kg/L	No

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

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

            ANSWER: The density of both the Styrofoam and the ice is lower than 1 kg/L. This is why both materials are able to float. All the other objects have a higher density, meaning that they will sink.

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

            ANSWER: Depending on where the blue object is placed in the water, it is able to sink or float.

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.

            ANSWER:  The densest object from the table is gold. According to the table, gold has a density of 19.31 kg/L.

10.  List something you learned from this activity.

( This list also fulfills the tasks for #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.)

            ANSWER: I have learned that an object will float if the density is lower than 1 kg/L. Some of the other lessons I learned from this simulation include:

Blue

Material= Apple

Mass= 0.64 kg

Volume= 1 L

Density= 0.64

Yellow

Material: Gold

Mass=65.14

Volume=3.38

Density=19.27

Green

Material= Gasoline

Mass= 4.08

Volume= 5.83

Density= 0.7

Red

Material=Ice

Mass=3.1

Volume= 3.38

Density= 0.92

Purple

Material=Diamond

Mass=3.53

Volume=1

Density=3.53

5. The following Science Standards that were met through these activities completed in Activity 5

A.4.1 When conducting science investigations, ask and answer questions that will help decide the general areas of science being addressed.

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.4.3 Select multiple sources of information to help answer questions selected for classroom investigations
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

C.4.7 Support their conclusions with logical arguments
C.4.8 Ask additional questions that might help focus or further an investigation