pH Lab

        pH LAB

HYPOTHESIS: Lemon juice, dish cleaner, vinegar, and ammonia are going to be acidic, and the others basic.


MATERIALS
computer
household solutions
Vernier computer interface
7 small test tubes
Logger Pro
test-tube rack
Vernier pH Sensor
blue litmus paper
wash bottle
paper towel
distilled water
stirring rod
ring stand
red cabbage juice
utility clamp
250 mL beaker
sensor soaking solution  
Dropper




Part I  Litmus Tests
Obtain a pair of goggles so that you may protect your eyes from any acidic splash from the contents you are about to be exposed to. Label 6 test tubes with the numbers 1–6 and place them in a test-tube rack. Measure 3 mL of vinegar into test tube 1. Refer to the data table and fill each of the test tubes to about the same level with its respective solution. Ammonia solution is toxic. Its liquid and vapor are extremely irritating, especially to eyes. Handle these solutions with care. Do not allow the solutions to contact your skin or clothing. Wear goggles at all times. Notify your teacher immediately in the event of an accident. Use a stirring rod or dropper, to transfer one drop of vinegar to a small piece of blue litmus paper on a paper towel. Transfer one drop to a piece of red litmus paper on a paper towel. Record the results. Clean and dry the stirring rod each time. Test the other solutions using the same procedure. Be sure to clean the stirring rod or dropper each time.

Part II  Red Cabbage Juice Indicator
After you have finished the Part I litmus tests, add 3 mL of red cabbage juice indicator to each
of the 7 test tubes. Record your observations. Dispose of the test-tube contents as directed by
your teacher.

Part III  pH Tests
Connect the pH Sensor to the computer interface. Prepare the computer to monitor pH by opening the file “21 Household Acids” from the Chemistry with Vernier folder. Raise the pH Sensor from the sensor storage solution and set the solution aside. Use a wash
bottle filled with distilled water to thoroughly rinse the tip of the sensor as demonstrated by
your instructor. Catch the rinse water in a 250 mL beaker. Get one of the 7 solutions in the small container supplied by your sensor. Raise the solution to the pH Sensor and swirl the solution about the sensor. When the pH reading stabilizes, record the pH value in your data table.

Household Acids and Bases
Prepare the pH Sensor for reuse. Rinse it with distilled water from a wash bottle.
Place the sensor into the sensor soaking solution and swirl the solution about the sensor briefly. Rinse with distilled water again. Determine the pH of the other solutions using the Step 9 procedure. You must clean the sensor, using the Step 10 procedure, between tests. When you are done, rinse the tip of the sensor with distilled water and return it to the sensor soaking solution.


PROCESSING THE DATA
1. Which of the household solutions tested are acids? How can you tell?
Lemon juice, Dish cleaner, Ammonia were acidic. We could tell by the blue litmus paper.
2. Which of the solutions are bases? How can you tell?
Vinegar, Ammonia, Laundry Detergent. We could tell by the shade the blue Litmus paper gave off.
3. What color(s) is red cabbage juice indicator in acids? In bases?
In acids it is a pink or green color and in some bases it would not mix at all.
4. Can red cabbage juice indicator be used to determine the strength of acids and bases? Explain. I think it does not because we had a variation in the shade or the colors and it was difficult to find any distinguishable colors or patterns within our experiments.
5. List advantages and disadvantages of litmus and red cabbage juice indicators.  
The advantage of Litmus is it gives you a color easily compared on the pH scale but the disadvantage is it isn't exact and the color can sometime not be perfectly matched so we have to guess somewhere in between. Red cabbage is good when it come to large amounts of the color but bad if you want a more exact answer.



CONCLUSION: My hypothesis was incorrect and vinegar and Ammonia were not as acidic as I had expected and were instead more of a basic compound.

ASU Chemstry

In our trip to ASU ground I learned so much matireal it was overwealming. But I was able to have fun while doing it. I saw vacummes being made inside of soda cans! I also saw how much strenght it truly took to get enough air pressure to create a vacum. It was simply amazing. When students came in to talk to us about what we wanted to do and what they were currently doing. It was a grand time to spend with friends and to learn about all the fun carrers in science. I look forward to our next feild trip and hope that it is as fun as this one was and that I may better myself in the studies of science. It was truly worth every second, and icorperated learning so you could not possibly get bored.

Creating A Polymer

Creating a Polymer Lab

Question: 
What materials are needed to create a polymer?
Hypothesis:
If you add the a higher amount of glue and a lesser amount sodium borate, and mix them together,  they will then form a mixture and create a polymer.

Materials:

500 mL water
25mL Elmer's glue
1 tsp. Borax
1 graduated cylinder
1 600 mL beaker
1 250 mL beaker
Stirring rod

Procedure:

In the measuring cup, add one tablespoon of borax powder to 100 mL of water and stir. Measure out 1/2 cup of Elmer’s glue and add it to 1/2 cup of water in a separate beaker. Now that you have both the borax and the Elmer’s glue solutions, now mix two tablespoons of borax solution to the glue solution. You must stir the new solution vigorously for a little while and you will notice the solution start to change in texture and appearance. There might be some liquid left, you can pour out the runny stuff.

1) How is slime visco-elastic?
Slime is visco-elastic because it is elastic and is thick

2)What are the physical properties that change as a result of the addition of sodium borate (borax) to the Elmer's glue?
The mixture became more like a solid than a liquid. It becomes thicker and is not so slimy feeling like glue.

3) What would be the effect of adding more sodium borate?
If you added more sodium borate, the polymer would probably be thicker, take longer to break, and dry faster. I also think that the glue smell would be even more weak and that it would bounce higher.

4) How does the water affect the elasticity of the polymer? What is elasticity?
The water makes it slimy and more elastic-like. It helps it to not dry out; therefore, the polymer is able to stretch without crumbling.6)What is the structural formula of the poly(vinyl alcohol) monomer of the repeating unit?
C2H3OH

Polymer Tests:

Slow progressing poke - Slime wrapped around finger before eventually breaking

Quick, Fast Poke - Finger bounced off slime

Slow pull - Slime stretched before eventually breaking into two pieces

Quick yank - Slime ripped in half almost immediately

Bounce test - Bounced about 13 cm up

The Polymer took 1:52 to flatten out

Chemistry Reflection
In the video Bill Nye: 100 greatest discoveries: Chemistry 1/3 Bill, The speaker, talked about 3 of the greatest discoveries that helped push man-kind in the direction of understanding chemistry and what makes us and the objects around us up. One of the greatest discoveries was of oxygen itself. It proved that there were gasses all around us. One that went along with this was the discovery that everything was not just a single atom, as thought before, but many molecules. This made it possible to believe that combining them was in the human race's grasp. But it was still nothing more then a possibility. Until a scientist left to chemicals out by accident and when the chemicals where pulled out they had formed crystals that were familiar to him. Both ingredients that created the crystals were inorganic, meaning they came from not living things. He studied the crystals and realized it was a substance that he had created, or found once before inside the kidney of animals. He was the first to show that it was possible to make organic material out of inorganic things. Another intelligent man created a chart that could be used to categorize the molecules and show what they could and could not combine with. He did this with all the molecules but one. Benzene. No one could figure out how to draw or the chemical structure of this Molecule. Until a man fell asleep thinking of a solution to this problem. He dreamed of a snake, eating his own tale. He awoke and figured it out. This molecule actually looped. Later it was confirmed.

Freezing And Melting Of Water


Question: What is the Freezing and Melting point of water?


Hypothesis:It freezes at 0.0 C and melts at 3.0 C.


Materials:
Computer                                 Vernier Computer Interface
400 mL Beaker                        Logger Pro
Water                                       Temperature Probe
Ice                                            Ring Stand
Salt                                           Test Tube
10 mL Graduated Cylinder           Stirring Rod


Procedure:
Please Gather The following
A ring stand, a 400mL beaker, ice cubes, salt(5 table spoons), A glass test tube, a Vernier temperature probe, a graduated cylinder. a stirring rod, a computer, and later some water. Put protective glasses on face. Take the Vernier Interface and plug the usb into the computer. Now that the ring stand and adjust it to a little bit taller then the 400 mL beaker. Now go fill 200 mL of water in the 400mL beaker. Bring it back and leave to obtain some ice. When you have the ice put it inside of the beaker. Now take the graduated cylinder and measure 5mL. Once this is done, pour it into the test tube. Take your temperature probe that you attached the computer and place it inside the test tube of water. Now apply the salt you gathered in the beginning. The salt will go inside the 400mL beaker. Stir with the rod and wait till the salt has completely dissolved with the water. Take the Test tube, Probe and place it in the water. Click collect on Logger Pro. Once you have clicked collect a red bar should start moving on the screen. Grab the very top of the test tube and begin stirring it in the water. If done correctly you should see the temperature gradually go down. Once you have stirred it for 10 minutes the computer should stop recording data. When this is done remove the frozen test tube and hold it up, by the ring stand. Do not let it touch any surface. Now that that is done, go dump out the water inside of the 400mL beaker, as well as the ice. Fill it with warm tap water. Now place it on the ring stand, click collect again, and watch the ice melt. Once it is done melting you may take it out and begin packing your things to go away neatly, as they once were.

Results:
Our ice was completely frozen at exactly -3.2 C and melted at 0.1 C. I think that we successfully did the assignment that was assigned to us. We managed to get good pictures of the test tube frozen. This test if executed correctly should work for everyone.

Polymer Basics     Name: Sinai Trapero

Use the sites on the Matter & Atoms page of the Kid Zone at http://sciencespot.net/ to complete this worksheet.

Site #1: Hands On Plastics
1. Plastics are polymers, which is something made of many units similar to a chain. Each link in the chain is the “mer” or basic unit usually made out of carbon, hydrogen, oxygen, silicon. To make the chain, many links or units are hooked or polymerized together.
2. Many common classes of polymers are composed of hydrocarbons, which contain the elements carbon and hydrogen. List seven elements that are also found in polymers: oxygen, chlorine, fluorine, nitrogen, silicon, phosphorus, sulfur.
3. What is one of the most famous silicon-based polymers? Silly Putty
4. What are the general attributes (properties) of polymers? A. Polymers can be very resistant to chemicals.
B. Polymers can be both thermal and electrical insulators. C. Polymers are very light in mass with varying degrees of strength.
D. Polymers can be processed in various ways to produce thin fibers or very intricate parts.
5. What percentage of our trash are plastics? 9.9%
6. What does WTE mean? Waste-to-Energy
What are two benefits of WTE? 1 –
We can use plastics that cannot be recycled. 2 – Incineration of polymers produces
heat energy.


Site #2:  History of Plastics
Read the information on this page to help you complete this section. Fill in the blanks with the year it was first
produced and the last name(s) of the person credited with the discovery/development. Use the information to list the
substances with dates from the oldest to the most recent in the box.

Rayon – Developed in 1891 by Bernigaut
Silly Putty - Developed in 1949 by Wright
Cellophane - Discovered in 1900 by Brandenberger
Parkesine - Discovered in 1862 by Parker
Nylon - Developed in 1939 by Carothers
Bakelite - Developed in 1907 by Baekeland
Velcro - Developed in 1957 by Maestral
Saran - Discovered in 1933 by Wiley
PVC (Vinyl) – Developed by Simon
Polyethylene – Developed in 1936 by Fawcett and Gibson
Teflon – Discovered in 1938 by Plunkett
Celluoid - Developed in 1869 by Hyatt



Plastics Timeline
Oldest to Most Recent
1 Parkesine
2 Celluloid
3 Rayon
4 Cellophane
5 Bakelite
6 Saran
7 Polyethylene
8 Teflon
9 Nylon
10 Silly Putty
11 Velcro

Site #3:  Polymers – They’re Everywhere

1. Click the “What are Polymers” link at the bottom of the screen and answer these questions. A. Polymers are tiny molecules strung in long repeating chains. B. What are three polymers found in our bodies? DNA, proteins,starches
2. Click the link for “In Nature” and use your mouse to find eight polymers in the picture. List them below.
Amber, silk, turtle’s shell, cow’s milk, animal horns, latex , lac, rosin
2. Click the “At Home” to learn about polymers that can be found around our homes. Use your mouse to find eight polymers and list them below.
Polyethylene, , neoprene, acrylics, rubber,Bakelite ,vulcanized rubber vinyl,polystyrene
3. Click the “Recycling” link and use your mouse to find eleven items made from recycled polymers in the park. For each item listed below, write down what it was used to make after being recycled. The number of blanks indicates the number of items for each polymer.
Peanut butter jar: Sweatshirt, Tote bag
Foam cup: Insulated jacket, Concrete
Bread bag: Trash can,Landscape Timber
Milk jug: Dog house, Picnic Table, Plastic Fence
Sandwich box: Playground equipment, flying disk (Frisbee)


Site #4 – Polymer Flash Activities
1. Click the link to make a virtual polymer and choose polyethylene.
A. What type of monomer is used to make this polymer? Ethylene
B. What elements and how many of each is in one of these monomers?
C=Carbon 2 H=Hydrogen 4
C. What starts the process? Initiator


2. Click the link to try the matching games.  Record your times or scores in the blanks below.
A. Breakfast Game– 1st Try = 9491  2nd Try = 9351  3rd Try = 9801
B. Polymer Game - – 1st Try = 9266   2nd Try = 9213  3rd Try = 9426