Thursday, July 26, 2012

Activity Five: Density, Activity Six: States of Matter and Intermolecular Forces, Activity Seven: Acids and Bases, Activity Eight: Exploration of Chemistry

Activity Eight: Exploration of Chemistry 
1. Concentration and Molarity II: Dilution and Evaporation PhET-Chemistry Labs
Introduction: In the first part of this lab, you learned about the actions of solid salts added to water to form solutions of various concentrations.  In this exercise, you will use a powerful and simple formula to determine the concentration of a solution when it has been diluted with additional water or made more concentrated due to evaporation of water.
Some handy vocabulary for you to define:
Molarity __concentration measured by the number of moles of solute per liter of solution.
Dilution _action of making something weaker in force, content, or value
Evaporaton__ the process of becoming a vapor
Procedure: PhETàPlay with the Sims à Chemistry à Concentration
Part 1: Dilution
At this point you should be familiar with the Concentration simulation.  Because some time may have passed, take a few minutes to re-learn the simulations.  Pay particular attention to the effect of evaporation and addition of water to the solution’s concentration
How does the concentration change as additional water is added? _The concentration becomes a lighter color.__
Why? __It is being diluted by the water.___ _____________________________________
How does the concentration change as evaporation occurs? _When the evaporation occurs the concentration becomes the bright color of the drink mix.
Why is this? ___There is less water to diluted it with because it is being evaporated making it the concentration only the drink mix.
Does evaporation change the concentration of a saturated solution? Yes________________________________________
Why is this? _______The concentration is becoming less saturated with water.___
Using the concentrated solution spigot, add a ½ Liter of Drink Mix to an empty beaker.  What is the concentration?
__5.833_  Is this solution saturated?  _____No_______  How do you know? ______There is no water.
Fill the beaker with another ½ Liter of water.  What is the new concentration?2.893 mol/L_______________
Complete the table below, using in an empty beaker, writing the concentration in the boxes provided.
Only .25L of spigot solution
.25L spigot+.25L water
.25L spigot + .50 L water
.25L spigot + .75 L water
4.000
2.376
1.485
1.176
Repeat the exercise, using in an empty beaker.
Only .25L of spigot solution
.25L spigot+.25L water
.25L spigot + .50 L water
.25L spigot + .75 L water
.500
.243
.169
.120
What do you notice about the concentration change as each addition of .25L of water is added to the concentrated spigot solution? ___________The color got lighter and the concentration went down._____ ___________________________
______________________________________________________________________________________________________
The formula  is a great way to calculate the concentration of a solution that undergoes dilution or concentration.  Refer to the concentration and volume of the original solution, and  refer to that solution after it has been diluted or concentrated.
0.20 L of has a concentration of 5.0 M. (M1 = 5.0 M and V1 = 0.20 L) If the solution’s volume, V2 is increased with water to .50 L, calculate the new concentration, M2.     Check your work in the sim AFTER your calculation.
Your Calculated M2: ________1.045_______________ . 
Complete the table below using .  Remember to calculate first, and then check in the sim.
M1
V1
M2
V2
.40 M
.20 L
.01
.80 L
.40 M
.50 L
.22
.90 L
.40 M
.30 L
.15 M
.8
Part 2: Evaporation: Making Solutions MORE concentrated   
Create a solution of   with a concentration 1.0 M of and a volume of .50 L .  If evaporation reduces the volume to .40 L without changing the dissolved solute, calculate the new concentration of the solution. Check your work in the sim AFTER your calculation.
Your Calculated M2: ____________1.25___________ .  New concentration shown in the simulation: ________________________
Complete the table below using  . Remember to calculate first, and then check in the sim.
M1
V1
M2
V2
.40 M
.80 L
.8
.40 L
.40 M
.90 L
1.78
.25 L
.40 M
.90 L
1.1 M
.33
Conclusion Questions and Calculations                           SHOW WORK
1.       Dilution causes the concentration of an unsaturated solution to increases / decreases / remains the same.
2.       Evaporation causes the concentration of an unsaturated solution to increases / decreases / remains the same.
3.       As a saturated solution (with no solids) is diluted, its concentration increases / decreases / remains the same.
4.       As a saturated solution (with no solids) is evaporated, its concentration increases / decreases / remains the same.

2. Density Work Out
Intended for 2nd Graders
By: Nicole Pater

Define:
Mass Volume:
Density:
Why do you think some of these objects float and some sink?
Does mass, volume, or both cause an object to sink?

Click on mystery. Try putting a block that floats in the water and then put another one on top of it. What happens?


Can two floating blocks on top of each other cause the other one to sink?


Bonus Question: If you wrap a box that sinks in something that floats will it float or sink?

a.         C.8.8.  Use computer software and other technologies to organize process, and present their data.
-Students use simulator.
 A.8.1.  Develop their understanding of the science themes by using the themes to frame questions about science related issues and problems.
-Students answer questions give to them.
B.4.1 Use encyclopedias, source books, texts, computers, teachers, parents, other adults, journals, popular press, and various other sources, to help answer science-related questions and plan investigations.
- Use dictionary to define terms. 







Activity Seven: Acids and Bases
1. The Color of a solution identifies if it is an acid, base, or neutral solution.
    False

2Which solution is basic?
      More than one

3Which solution is acidic?
     C

4. Which solution is basic?
   B

5.  Which solution is more acidic?
     More than one

6.  How will adding water effect the pH?
       Increase the pH

7.  How will equal amount of water effect the pH?
     Decrease the pH

 8.  What is the order from most acidic to most basic?
       abc 

9.  What is the order from most acidic to most basic?
       bac

10.  If spit has a pH = 7.4, what does that tell you about the water equilibrium?
         Something was added that made the equilibrium shift left

Name:_________Nicole Pater___________
Introduction to Strong and Weak Acids and Bases PhET Lab (rvsd 5/2011)
        How does the strength of an acid or base affect conductivity?pH?
Introduction:
When you test your pool’s pH, what are you those little vials or paper strips telling you?  When you hear an acid called “strong” or “weak”, what do those terms refer to?  In aqueous solutions, compounds can exist as molecules (undissociated) or ions (dissociated).  When an acid or a base exists in solution nearly completely as dissociated ions, we refer to that acid or base as strong.  A weak acid or base will donate ions to the solution, but will remain primarily as undissociated molecules.

Notation:
Acids are abbreviated HA, with the H representing the proton (H+) the acid donates to the solution.  The A is referred to as the acidic anion (A-) that is left in solution as the proton is donated.
Strong Bases are abbreviated MOH, with the OH representing the hydroxide ion (OH-) the base donates to the solution.  The M is cation (M+) that is left in solution as the hydroxide is donated..

Autoionization:
Even without any acid or base added a very small number of water molecules will form protons (H+) and hydroxide ions (OH-).  The protons will then form hydronium ions, the acid ion.

Procedure: PhET Simulations à Play With Sims à Chemistryà Acid-Base Solutions à  
The concentration of the acids and bases used in the  at 0.010 (10-2) Molar.

·         Begin with a strong acid and lower the pH probe into the beaker.  What is the pH of this solution? 
·         Test this strong acid with both pH paper and the conductivity probe.  What color does the pH indicator become?  Is this strong acid an electrolyte?  Does current travel through this solution?
·         Repeat the above tests with the weak acid, the strong base, and the weak base, and water.  Collect your observations in the table below:


Strong Acid
Weak Acid
Strong Base
Weak Base
Water
pH meter read
(value)

2.00
4.50
12.00


9.50
7.00

pH paper
(color)
red
orange
blue
green
Light orange
Conductivity
(bright/dim/none)
bright
dim
bright
dim
dim
Exists as Mostly
(ions/molecules)
ions
molecules
ions
molecules
ions
Procedure:
This simulation allows you to change the concentration of a strong and weak acid and base.
Complete the table below for some strong acids and bases and weak acids and bases by adjusting the concentration.
Strong Acids
Strength
Initial Acid Concentration (mol/L)
[HA] (mol/L)
[A-] (mol/L)
[H+] (mol/L)
pH
.010 M
Negligible
1.00x 10^2
1.00x 10^2
2.00
.050 M
Negligible
5.00x 10^2
1.00x 10^2
1.30
.100 M
Negligible
1.00x 10-1
1.00x 10^-1
1.00
1.00 M
Negligible
1.00x 10^0
1.00x 10^0
0
Weak Acids
Strength (approximately)
Initial Acid Concentration (mol/L)
[HA] (mol/L)
[A-] (mol/L)
[H+] (mol/L)
pH
.015 M
1.50x 10^2
3.87x 10^-5
3.87x 10^-5
4.41
.150 M
1.50x 10^2
1.22x 10^-4
1.22x 10^-4
3.91
.015 M
7.86x 10^-5
1.49x 10^-2
1.49x 10^-2
1.83
.150 M
7.20x 10^-3
1.43x 10^-1
1.43x 10^-1
0.85
Strong Bases
Strength
Initial Acid Concentration (mol/L)
[MOH] (mol/L)
[M+] (mol/L)
[OH-] (mol/L)
pH
.010 M
Negligible
1.00x 10^-2
1.00x 10^-2
12.00
.050 M
Negligible
5.00x 10^-2
5.00x 10^-2
12.70
.100 M
Negligible
1.00x 10^-1
1.00x 10^-1
13.00
1.00 M
Negligible
1.00x 10^0
1.00x 10^0
14.00
Weak Bases
Strength (approximately)
Initial Acid Concentration (mol/L)
[B] (mol/L)
[BH+] (mol/L)
[OH-] (mol/L)
pH
.015 M
1.50x 10^-2
3.87x 10^-5
3.87x 10^-5
9.59
.150 M
1.50x 10^-1
1.22x 10^-4
1.22x 10^-4
10.09
.015 M
7.86x 10^-5
1.49x 10^-2
1.49x 10^-2
12.17
.150 M
7.20x 10^-3
1.43x 10^-1
1.43x 10^-1
13.15
Conclusion Questions:
1.      A strong acid is very concentrated / exists primarily as ions. (circle)
2.      A weak base is a nonelectrolyte / weak electrolyte / strong electrolyte.
3.      A strong base is a nonelectrolyte / weak electrolyte / strong electrolyte.
4.      At the same concentration (Molarity) a strong acid will have a higher / lower / the same pH as a weak acid.
5.      As concentration of a weak acid increases, the pH increases / decreases / remains constant.
6.      As concentration of a weak base increases, the pH increases / decreases / remains constant.
7.      As the concentration of a weak acid increases, the number of ions increases / decreases / remains constant.
8.      As the concentration of a weak acid increases, conductivity increases / decreases / remains constant.
9.      As the strength of a weak acid increases, the proportion of ions to molecules increases / decreases.
10.  As the strength of a weak acid increases, the conductivity increases / decreases / remains constant.
11.  What are the pH values of a weak acid with a concentration of 0.10 and a strong acid with a concentration of 0.01, ten times lower?     Weak acid, 0.10 M :___5.00_________         Strong Acid, 0.01 M :_____2.00_______
12.  Explain the significance of the results of your calculation above. _Strong acid has lower pH value than the weak acid due to the fact there are more ions in the strong acid. 
         


Activity Six: States of Matter and Intermolecular Forces
1. Convert 0°F, 32°F, 70°F, and 212°F to Kelvin
0 degrees F= 255.222 degrees Kelvin
32 degrees F= 273 degrees Kelvin 
212 degrees F= 373 degrees Kelvin 

2.
Name:                         Nicole Pater                                       Date:                                                              
Class:                                      Chemistry                                           States of Matter Simulation Lab

States of Matter Simulation Lab

Before you open the simulation:

PREDICT
1. Draw a diagram below showing what you think the molecules will look like for each state of matter, solid, liquid, and gas. Write a sentence below each diagram predicting what the motion of the molecules will be like.


Solid
Liquid
Gas
Diagram of molecules


…………
…………
…………
………….




….. . .    .. … . .
 . ..     . .      ….
…….    ..  ……
 …. .    .. . . . . .
.                   .       .     .       .
 .                       .                     .
 .       .            .                .
   .                 .        .           .
.         .         .                .
   .             .        .            .      .
.          .                  .
Sentence explaining how molecules will be moving.
Stay together. Not a lot of movement
Still together but has more movement.
Not together and moving fast.

2. If you start with a substance as a solid, what will happen to the molecules as you add thermal energy (heat)?                                    The molecules spread apart and start to move around at a very fast pace.

ONCE YOU HAVE COMPLETED THIS PAGE, YOU MAY BEGIN THE SIMULATION.
Open the simulation. You will find it in a folder on your desktop labeled “States of Matter Simulation.”

INVESTIGATE:

3. Use the menu on the right side of the program to select Water and Solid. Draw and describe what you see in the space below.

Diagram
Description
.O.     .0.   .0.
     .0.    .0.     .0.
.0.     .0.     .0.    .0.
     .0.    .0.     .0.

Together but shakes.

4. Now, use the slider on the bottom of the program to Add Heat. Notice the thermometer at the top of the program. What temperature scale is this thermometer showing?                     Kelvin            

5. What happens to the water as you increase the temperature?          The molecules let go of each other and move faster and faster.

6. What is the melting/freezing point of water in Kelvin?            Freezing point= 273.15 Kelvin

7. Add heat until the temperature is just below and then just above the melting point of water. How is water different below its melting point and above it?                 Some molecules move apart some stay together.

8. Draw and describe what water looks like as a liquid.

Diagram
Description

.O.  .0. .0.
 .0. .0. .0.
.0. .0. .0. .0.
 .0. .0. .0.







Stay together but still has some movement.



9. What is the boiling/condensation point of water in Kelvin?   Boiling point= 373.15 Kelvin                                                          

10. Continue to add heat until you are just below and then just above the boiling point of water. How is water different below its boiling point and above it?       As the molecules move faster they spread away from each other.

11. Draw and describe what water looks like as a gas.

Diagram
Description
.O.                                       .0.                                 .0.
     .0.                             .0.                            .0.
.0.                      .0.                      .0.                         .0.
     .0.                            .0.                         .0.


Fast movement and spread apart.

12. Choose one of the other three substances listed in the menu on the right. Investigate what happens when you add and remove heat from this substance. Use the buttons on the right to see this substance as a solid, liquid, and gas. Draw and describe its properties in the table below.

Substance Selected: Argon                          


Solid
Liquid
Gas
Diagram of molecules



……………
……………..
……………
……………



……  ……      …
…       ……         ……..
……    ……   …
…    ……     ……

.                   .       .     .       .
 .                       .                     .
 .       .            .                .
   .                 .        .           .
.         .         .                .
   .             .        .            .      .
.          .                  .
Sentence explaining how molecules are moving.
Stays together
Together but has some movement
Fast movement and spread apart






ANALYZE:

13. How was this substance similar to water in each state of matter? How was it different?             The states of matter were the same but when heat was added the reactions were different.                  

14. Were your predictions (see p. 1) correct or incorrect? Explain.      Yes, the heat makes molecules move faster.
BONUS: Optional, worth up to 10 points added to the lab’s final grade

15. Choose a substance other than water from the menu on the right side of the program. Use the slider to add and remove heat. Based on what the molecules do, figure out the approximate temperatures of the melting point and boiling point of this substance. (Hint: The temperatures given when you click solid, liquid, and gas are NOT the melting and boiling points.)

Substance:                              Argon            

Melting Point:            91 K                           

How did you figure it out?               Movement and spread apart                                                          

Boiling Point:                                                 124 K 

How did you figure it out?               Stayed together but starting to move apart                                  

3.Describe how the water molecules are aligned and attracted to each other. Which atoms are attracted to which other atoms?
Water molecules are next to hydrogen atoms and oxygen atoms but with no movement.


4. On your blog, report a temperature and pressure required to make oxygen a liquid.
100 ATM for oxygen to be at liquid state.


5. List and describe two science standards that this activity addresses.
E.4.2 Show that earth materials have different physical and chemical properties, including the properties of soils found in Wisconsin. 
- We explored solid, liquid, and gas. 


C.8.8. - Use computer software and other technologies to organize, process, and present their data.

-Used the simulators on the website to do each activity. 




Activity Five: Density 


Lithium

3 protons
4 neutrons
3 electrons
density- .535 grams per cm cubed

Boron
5 protons
6 neutrons 
5 electrons
density- 2.34 grams per cm cubed 

Define Density
Density is mass divided by volume. It is a measurement of the amount of matter in a given volume of something. (d = m / V) 


Student Guide for Density Simulation:                              Name: _Nicole Pater____

(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
wood
F
0.40 kg/L
Styrofoam
F
0.15 kg/ L
ice
F
0.92 kg/ L
brick
S
2.00 kg/ L
Aluminum
S
2.70 kg/ L

MC900432579[1]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? 
The volume cannot change.
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?
The triangle does not move for each object because you cannot change its density.
                                            
7.                          How does the density of aluminum (2.70 kg/L)  help explain what you see?
MC900432579[1]____It shows it has the highest density out of all the objects and it cannot be changed.

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 _15.00_kg/L_.  We have learned that _density does not change____________________________________
8.   MC900432579[1] Density  = ----------       “___mass____ over __volume____ equals ______density_________”

In the “Blocks” box, click on Mystery:

 People-Talking-Profile-ImageTest the boxes in the water- just drag and drop!!! 

 
  
MC900432579[1]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
19.27
Gold
  B
100-L
100.64 L
.64 L
.64
1
Water
  C
100-L
104.08 L
4.08 L
4.08
1
water
  D
100-L
103.10 L
3.10 L
3.10
1
Water
  E
100-L
101.00 L
1.00 L
3.53
3.53
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
Red is smaller
2nd observation
Even though green is bigger than red it still floats.
3rd observation
It takes the red box longer to float to the top.

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!!!!

MC900432579[1]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.
____It depends what you are making the boat out of and how big the refrigerator and television are. My guess is it would sink. When I put a box that floated in the water and then put all boxes on top of it the bottom box would sink.
…you can write on the back if you need more room to write!       Signed, your te




Blocks
Mass (kg)
Volume (L)
Density (kg/L)
Identification of Material
Know density of material identified
A
65.14 kg
3.38 L
19.27 KG/L
Gold
19.3 KG/L
B
0.64 kg
0.64 L
1.00 KG/L
Water
1.00 KG/L
C
4.08 kg
4.08 L
1.00 KG/L
Water
1.00 KG/L
D
3.10 kg
3.10 L
1.00 KG/L
Water
1.00 KG/L
E
3.53 kg
1.00 L
3.53 KG/L
diamond
3.53 KG/L
Standards:

 C.4.5 Use data they have collected to develop explanations and answer questions generated by investigations C.4.2 Use the science content being learned to ask questions, plan investigations, make observations, make predictions, and offer explanations   C.8.7.   Explain their data and conclusions in ways that allow an audience to understand the questions they selected for investigation and the answers they have developed
                C.8.8    Use computer software and other technologies to organize, process, and present their data.


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