Activity 8: Exploration of Chemistry
For activity 8, students have a choice to explore other topics of chemistry presented in the PhET simulations. 
Tasks to be completed:

1.     Choose any Teaching Idea from any of the Chemistry Simulations (http://phet.colorado.edu/en/simulations/category/chemistry ) and post your results/data and/or answers on your blog

The topic that I choose to do was balancing chemical equations. The simulation link is: http://phet.colorado.edu/en/simulation/balancing-chemical-equations Here are my results from doing the homework for this simulation:

Balancing Chemical Equations

1.  Use the simulation to adjust the coefficients and balance the following equation.  Select the balance scales and bar charts to help.  Fill in the proper coefficients when you are successful (yellow smiley face).

_1_N₂ +_3_ H₂ à _2_ NH₃

 2.  Draw or take a screen shot of the particle view of the balanced equation as shown in the simulation.

3.  Describe the purpose of the balance scales and bar charts in the simulation.

                The purpose of the balance scales and bar chart in this simulation was to not only have the students do the activity, but once they have found the balance between the chemicals, they can see how much Hydrogen, oxygen or some on that going into the chemical they just created.  This was a great way to show me how having one more element than another of something can make a totally different chemical than you wanted to make in the first place.

4.  In order for a chemical equation to be properly balanced, what must be true?

For all chemical equations to be properly balanced, it has to have to same amount of involved in the reaction. There has to be an equal number on each side of the scale.

5.  Balance the other two examples.

               

Separate of water

               

_2_ H₂O à _2_ H₂ + _1_ O₂

Combust of methane

_1_ CH₄ + _2_ O₂ à _1_ CO₂ + _2_ H₂O

6.  The number placed in front of a formula is called a coefficient.  The small number within a chemical formula is called a subscript.  Why do we adjust coefficients when balancing chemical equations and not subscripts?

You cannot change the number of atoms, only the number of molecules. If you change atoms you change the whole chemical structure and then ultimately the chemical.

GAME

Record your score for each of the levels in the balancing game:

                                Score

Level 1                                  10/ 10

Level 2                                  9/10

Level 3                                  10/ 10

Balancing mask lesson:

For my lesson, I wanted to stay using the balance lesson with my own ideas. My lesson will be amid towards grades first to fourth grade. The goal objectives are:

My science objectives for the science education standards that this lesson will meet are:

1.              G.4.5 Ask questions to find answers about how devices and machines were invented and produced

The way this standard will be used in the lesson is by the children asking questions about how some devices were invented and are being used in the work field today to make sure that before products go out in the stores, they are balanced and safe to use.

2.              C.4.4 Use simple science equipment safely and effectively, including rulers, balances, graduated cylinders, hand lenses, thermometers, and computers, to collect data relevant to questions and investigations

This standard will be used by the students learning all of these new forms of equipment, if they ever have a question about why something is the way that it is in science, they now know what these tools are and how to use them, so they are starting to be more independent and being about to answer the investigations questions along.

3.              H.4.1 Describe* how science and technology have helped, and in some cases hindered, progress in providing better food, more rapid information, quicker and safer transportation, and more effective health car

This standard could be used in my lesson by seeing some of the classmates masks fail because they did not put an even amount of elements on each side of the mask. They will be able to help each other out by telling them what makes it not even, so that they will not make this mistake again. Science and technology will help the children to develop new ways of thinking and realizing that science can be used in any form.

The literacy objectives standards that this lesson will meet are:

1.      Actively engage in group reading activities with purpose and understanding.

This standard will be meet by the children hearing what it is that we are doing in this lesson and understanding the purpose so that they are not just making masks for the fun of it. They are comprehending the goals and trying to complete them as best as they can.

2.      With prompting and support, read prose and poetry [informational texts] of appropriate complexity

This last standard will be meet by the support of other students ad teachers around them, the students will be able to ask questions and complete this mask making activity balanced.

The materials that I will need to use for this lessons are:

-colored paper

-white masks

-buttons

-markers

-glue

What the lesson will be:
             Each student will get their own mask to director. The mask will be plane whit with only one black line going right down the center of it. The goals are for the students to make a mask that is evenly balanced between the two sides. The children will have many objects sitting at the center of their tables to pick from and glue onto their masks. Before the children will be creating this mask, we will have talked about what balance is, and how if something is off balance then one side will be heaver then the other. This is where the literacy standards will come into play. Children will have to be able to understand what the definition of balance is to make sure that when making there masks, each side has the same amount of weight and elements. Children will need to also understand the appropriate complexity of the directions to complete the mask with an equal balance. How this lesson will meet the science related standards are by the children now understanding what balance is, and how the littlest object can set it off, they will be able to complete a mask will equal sides of weight. The children can always ask questions about what being balanced really means, and how we will use balance in our everyday life. How some machines like a scale or a balancer are made to help people make sure that something is balanced evenly. I believe that this lesson will be a great way to engage the young students into learning something new, but still being able to have hands on experiment to learn by. Working and coming up with lessons for the younger grades can be difficult at times, but I think that this is a good lessons to teach them by. 

Activity 6

Activity 6: States of Matter and Intermolecular Forces



To begin this activity, review the Content Slides in D2L on States of Matter and Intermolecular Forces. We are all familiar with the states of matter (solids, liquids and gases) for many substances. In the First Activity we explored these states of matter for water. In Activity 6, we would like to take our overall understanding of states of matter to the molecular level. We will use the States of Matter simulation at http://phet.colorado.edu/ . There are two key characteristics of molecules that determine their state of matter. The first one is the temperature of the matter, and the second one is the intermolecular forces (how well atoms/molecules stick to one another) between atoms and molecules.

One of the first things to think about here is temperature. Temperature and thermometers have a very similar relation to speed and speedometers. For all practical purposes, a thermometer is really a speedometer for molecular speed or motion. At this site (another good NSF funded science education site)http://www.visionlearning.com/library/module_viewer.php?mid=48 , is a good overview of temperature with a good image of the temperature scales and conversions between different scales. Notice that the Kelvin scale starts at zero and goes up from there. This is like our car speedometer, in that at 0 Kelvin (K), molecular and atomic motions stop. As the temperature rises, atoms and molecules begin to move faster and faster.



The second thing to consider is the intermolecular forces (attractions) that exist between molecules. In the D2L content slides there are a few types of attractions described, notice all of these are defined by the attraction that exists between positive and negative charges. Water is a great example of a molecule that has strong attractions that we call hydrogen bonding. It is this strong attraction that makes water a unique molecule on our planet. It turns out that the hydrogen atoms tend to be positive in charge, and the oxygen atoms tends to be negative in charge.



Tasks to be completed for Acitivity 6

1. Convert 0°F, 32°F, 70°F, and 212°F to Kelvin

a.      0°F= 273.15

b.     32°F= 305.15

c.      70°F= 343.15

d.     212°F= 485.15

2. Complete the Teaching Idea: States of Matter Simulation Lab by Kelly Vaughan. Complete the lab worksheet as if you were a student, and then post this on your blog. You can scan it or just take a picture of it. 

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.

2. If you start with a substance as a solid, what will happen to the molecules as you add thermal energy (heat)?                Be adding heat to a solid the molecules will start to separate and turn into a liquid. If you have enough heat for a long time, it will continue to turn into a gas.

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.

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? The temperature is showing kelvin.

5. What happens to the water as you increase the temperature? When I add heat to the liquid, the molecules start to come apart and more freely around the whole can. Not staying together. When adding heat to solids, they perform the same way as the liquids do.

6. What is the melting/freezing point of water in Kelvin? The melting point of water in Kelvin is = 273.15K the freezing point is = 273.15K. They are the same

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?

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

9. What is the boiling/condensation point of water in Kelvin? The boiling condensation point of water is Kelvin is 373.15K

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? Water is different  when the temp is just below the boiling point at 370 K by the water molecules still jumping around on the bottom of the can, but more are becoming lose from the group and moving quite faster . Water is different when the temp is just above this point at 379K by all the molecules being off the bottom of the can, and more and more are reaching the top of can. The molecules are move faster and jumping much higher.

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

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

ANALYZE:

13. How was this substance similar to water in each state of matter? How was it different?

For each of the states of matter, I noticed that there was a lot of similarities and not to make differences. All the solids were very close together at the bottom of the can. The liquids were still connected but moving a little faster, and gas was jumping all over the place not in a group setting. One difference that I noticed was that under the oxygen even in the gas state, the molecules were moving in pairs. Two molecules were glued together jumping and spinning around. 

14. Were your predictions (see p. 1) correct or incorrect? Explain.

My prediction were very close to what the molecules showed me. I believe this is because I have avery good understanding of what a gas, liquid and solid look like and I know that the molecules had to look something like that.

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: Neon

Melting Point: 24K

How did you figure it out?

The way that I figured this our was I slowly started to heat up the temperature until the molecules started to spread apart and go from sitting on the bottom of the can to moving up to the top.

Boiling Point:      26K

How did you figure it out? The way that I figured the boiling point was to continue to raise up the heat until the molecules were no longer in a group at all and they were all on their own. Also known as a gas once it gets this hot.

3. In the States of Matter simulation, choose the Solid, Liquid, and Gas Tab at the top of the screen. Choose the water molecule and cool the water to 0 K. Describe how the water molecules are aligned and attracted to each other. Which atoms are attracted to which other atoms?

hot 25K movement, moleules have space inbetween them, fly around all over area, most fast, no order

cold 0k slow down, bunch together, no space between them, sink to bottom of area

Which atoms are attracted to which other atoms?

cold attracted to cold

hot repelled from hot

4. Switch to the Phase Changes Tab on the States of Matter simulation. Notice how on the bottom right there is a small red dot that indicates where the system is at as far as temperature, pressure and state of matter. Play with the simulation to notice changes, notice that when you push down the pressure can go way up and explode the box. On your blog, report a temperature and pressure required to make oxygen a liquid. This is sometimes how the oxygen exists in pressurized oxygen tanks, perhaps like ones you may use to go diving.

Triple point: Temperature 55K = Pressure= 0   ATM
                                          55K                     .05 ATM

The more pressure, the less amount of heat needed to liquify oxygen at a fast rate.
The less pressure, the more amount of heat is needed to liquify the oxygen faster.
temp 49K+
Adding more oxygen does not make the process go faster or slower.

5. List and describe at least two Science Standards that this activity addresses.

Standard D 4.3 “Understand that substances can exist in different states-solid, liquid, gas”

            This science standard is addressed throughout the whole activity. This activity deals with solid, liquid, and gases as being different elements in the beginning. Later on in the activity we learn how a liquid can turn into a gas. How a gas solid can turn into a liquid and so on.

Standard C 4.5 “Use data they have collected to develop explanations and answer questions generated by investigations”

            This activity addresses this standard because of how easy it was for me to answer the questions once I had completed the activity. While I was in the process of doing the tests with the simulations, I was keeping track of my numbers and collect important data. At the end of the test when it came time to answer the questions all I had to do was look at my written results and not have to do the test over again. Saves time and much easier to put into my own words. 

Activity 7

Activity 7: Acids and Bases

 

Water is everywhere!  So, lets spend one more activity learning about one of the key aspects of water.  Water has the ability to dissociate (break apart from HOH (or H₂O) into H+ ions and OH- ions).  We refer to solutions with lots of H+ ions as acids and solutions with lots of OH- ions as bases.  By adding chemicals with H+ ions acidic solutions can be made.  By adding chemicals with OH- ions basic solutions can be made.

Activity Tasks:

1. Review the Content Slides Acids and Bases on the D2L site.  

2. Complete the Teaching Idea “Concept Questions for Chemistry using PhET”  posted by Trish Loeblein on the pH Scale simulation at PHET (http://phet.colorado.edu/en/simulation/ph-scale). On your blog post the answers with your scientific explanations from the “Clicker Questions pH Scale” posted by Trish.

1. B. False. This is because when I moved the amount of acid to base ration on the PH scale simulation test, the color stayed the same.  So this would mean that the question is false, the color of a solution does not identified if it is an acid, base, or neutral solution.

2. D, because more than one of the photos shown above is a basic solution. 7 is natural on the pH scale, so anything higher than 7 is a basic.

3. C because the color red is acid, and there are a few bases (OH-) mixed in with the H₃O+. A is about 13 on the pH scale, B is showing a photo of water, and c could be a photo of vomit. 2 on the pH scale.

4. B, it cannot be A because that is showing equal amounts of acid to base. C is showing way more acid then bases.

5. D. A is showing the molecules of coffee, B is showing pop, and c is showing 13 in the pH scale. The correct answer is D because both coffee and pop are very acidic.

6. A. increases the pH. The more water lessens the acidity, so pH goes up.

7. B. more water lessens the basicity, so pH goes down. Decreases the pH.

8. A ABC, The lower numbers are acid, and the higher numbers are bases.

9. C BAC because water 7, acid 0 and base 14.  Water is 7 in pH scale, pop is 2.5 and b is showing 13 on a pH scale.

10. A, something (base) was added and made the equilibrium shift left. The pH scale from left to right goes 14-0.

 

3. Complete the Teaching Idea “Intro to Strong and Weak Acids and Bases” posted by Chris Bires on the Acid-Base Solutions simulation (http://phet.colorado.edu/en/simulation/acid-base-solutions) and post on your blog your data and answers to the questions posed.

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)	0.00 darkest red	6.00 light orange	11.00 medium blue	9.00 greenish-grey	7.00 dull yellow
Conductivity (bright/dim/none)	bright	dim	bright	dim	dull
Exists as Mostly (ions/molecules)	Mostly H30+	D, C

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	1.00 x 10 -2	1.00 x 10 -2	2.00
	.050 M	negligible	5.00 x 10-2	5.00 x 10-2	1.30
	.100 M	negligible	9.9 x 10-2	9.9 x 10-2	1.00
	1.00 M	negligible	9.90 x 100	9.90 x 100	0

Weak Acids

Strength (approximately)	Initial Acid Concentration (mol/L)	[HA] (mol/L)	[A-] (mol/L)	[H+] (mol/L)	pH
	.015 M	1.50 x 10-2	3.81 x 10-5	3.81 x 10-5	4.42
	.150 M	1.50 x 10-1	1.21 x 10-4	1.21 x 10-4	3.92
	.015 M	1.93 x 10-4	1.48 x 10-2	1.48 x 10-2	1.83
	.150 M	1.58 x 10-2	1.34 x 10-1	1.34 x 10-1	.87

Strong Bases

Strength	Initial Acid Concentration (mol/L)	[MOH] (mol/L)	[M+] (mol/L)	[OH-] (mol/L)	pH
	.010 M	neg	1.00 x 10-2	1.00 x 10-2	12
	.050 M	neg	5.00 x 10-2	5.00 x 10-2	12.70
	.100 M	neg	1.00 x 10-1	1.00 x 10-1	13
	1.00 M	neg	1.00 x 100	1.00 x 100	14

Weak Bases

Strength (approximately)	Initial Acid Concentration (mol/L)	[B] (mol/L)	[BH+] (mol/L)	[OH-] (mol/L)	pH
	.015 M	1.50 x 10-2	2.20 x 10-5	2.20 x 10-5	9.34
	.150 M	1.50 x 10-1	6.9 x 10-5	6.9 x 10-5	9.84
	.015 M	1.50 x 10-2	2.20 x 10-5	2.20 x 10-5	9.34
	.150 M	1.50 x 10-1	6.95 x 10-5	6.95 x 10-5	9.84

 

 

1.      A strong acid is very concentrated / exists primarily as ions.

 

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 : 4 Strong Acid, 0.01 M : 2

 

12. Explain the significance of the results of your calculation above.

On the pH scale if you go ten times lower, the pH will only drop one digit lower. For someone that has never read the pH scale before, it can be confusion because each number is 10x times bigger (or smaller) than the number preceding. Depending on which way you are going on the pH scale always make sure that you are writing your answer with 10x. pH scale is a logarithmic. This is where base 2 crosses the x axis horizontal axis, and one passes through the points with (x,x) coordinates.