Activity Eight: Exploration of Chemistry
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
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
Why?
__It is being diluted by the water.___ _____________________________________
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________________________________________
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.
False2. Which solution is basic?
More than one
3. Which 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.
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.”
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.
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)
|
2. Click on the first link
3. Click on the 
button
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
|
|
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]](file:///C:/Users/Student/AppData/Local/Temp/msohtmlclip1/01/clip_image007.gif){kind=small}
____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]](file:///C:/Users/Student/AppData/Local/Temp/msohtmlclip1/01/clip_image016.gif){kind=small}
Density =
---------- “___mass____ over __volume____
equals ______density_________”
In the
“Blocks” box, click on Mystery:
|
![MC900432579[1]](file:///C:/Users/Student/AppData/Local/Temp/msohtmlclip1/01/clip_image020.gif){kind=small}
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.
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]](file:///C:/Users/Student/AppData/Local/Temp/msohtmlclip1/01/clip_image022.gif){kind=small}
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.8.8 Use computer software and other technologies to organize, process, and present their data.
