Polymer Lab

Image 4 a strand of polymer with monomers in repeating order

Image 3 Our Borox solution

Image 2 our polymer in real life

 Image 1 Our polymer

Hypothesis: If we combine the two solutions than it will become thick and  strong.

Results: When we started with the two separate solutions the borax solution looked like a water with dust in it as expected. The glue solution looked like what it was glue diluted with water. When we proceeded to mix 40 ml of water into the glue solution it the glue began to mix with the borax solution making a solid. It appeared that the glue started expanding out and bonding with the water it made a thick blob that was kind of like silly putty. When we started performing vaious tests with the material we noticed a few things.
For one test we were asked to see how the polymer reacted when stretched fast or slowly. When we stretched it fastly and it snapped quickly however when it was stretched slowly it was able to get longer and thinner before breaking. It was also bouncy as we observed coming up on the table. We had tried to mix food coloring in to give it a green appearance but we did not mix it well enough so it came out splotched with green. As time progressed the blob started to become dryer because it was losing water making it brittle and crumbly. When it had the water it was more elastic and stretchable.
We were also shown how the molecules bonded  on the sheet. the polymer looked like the image 1.We saw that the borox solution B(OH)4 So the bonding part of the compound was the b’s, o’s and h’s in it.
 

Conclusions: Judging by our results I would say my hypothesis was only partially right because I said it would get thick and strong which it did I however didn't say it would go all the way becoming a solid. The chemical change that the borax and water brought caused the glue to become a solid. Throughout this lab we never really had any thing go wrong. The only thing that was slightly problematic was the coloring and that didn't really affect our final product. The lab was very successful.

There are a lot of extensions I would like to try with this lab. We are just scratching the surface of not only this polymers but all of the other ones too. With this we saw some pretty basic bonding with Borox, water, and Glue but we could try and change the variables with more or less borox an we could see if just the borox and glue would have the same reaction without water. Also, we could do research to see if we could find any other chemicals that react with glue and we could test that if we can get the materials. For a final change I was thinking we could add temperature or take it away to see if that affects the chemical process.

ChemThink; Chemical Reactions

1. Starting materials in a chemical reaction are called reactants
2. The ending materials in a chemical reaction are called products
3. The arrow indicates a chemical reaction has taken place
4. All reactions have one thing in common: there is a rearangment of chemical bonds.
5.Chemical reactions always involve old bonds breaking, new bonds being created, or both.
6. In all reactions we still have all of thesame reactants at the end that we had at the start.
7. In every reaction there can never be any destruction atoms or construction
8. Chemical reactions only rearrange the bonds in the atoms that are already there.
9.Let's represent a reaction on paper. For example, hydrogen gas (H2) reacts with oxygen gas (O2) to form water (H2O): H2 + O2 = H2O
If we use only the atoms shown, we'd have 2 atoms of H and 2 atoms of O as reactants. This would make 1 molecule of H2O, but we'd have 1 atom of O leftover. However, this reaction only makes H2O.

Remember: reactions are not limited to 1 molecule each of reactants. We can use as many as we need to balance the chemical equation.

A balanced chemical reaction show
a) What atoms are present before (in the reactants) and after (in the products)
b) How many of each reactant and product is present before and after.

10.  So to make H2O from oxygen gas and hydrogen gas, the balanced equation would be:
2H2 + O2----> 2H2O2
whis is the same as:

# of atoms in Reactants	Element	# of atoms in Products
4	H	4

2

O

2

11.  This idea is called the The Law of Conservation of Mass
12.  There must be the same molecules and the same number of molecules before the reaction (in the reactants) and after the reaction (in the products).
13. What is the balanced equation for this reaction? 2 Cu +1 O2 ----->  2CuO
14. Reactants- 2Cu, O2 Products- 2CuO
15. To balance this equation we would have to add CuO molecules because this reaction doesn’t make lone oxygen molecules.
16. When we add a molecule of CuO now the number of oxygen atoms is balanced but the number of Cu atoms don’t match. Now we have to add more cu atoms to the reactants.
17. the balanced reaction for this equation is 2 Cu +1 O2 ----->  2CuO
Reactants- 2Cu and 1 O2 Product- 2Cu and 1 O2
18. 2CH4 + 4O2----> 4H2O + 2CO2
19. N2+ 3H2----> 2NH3
20. 2KClO3-----> 2KCl + 3O2
21. 4Al + 3O2-----> 2Al2O3

summary

(1)Chemical reactions always involve the breaking or making of bonds.
(2)The Law of Conservation of Mass says that the same atoms must be used for reactants and products
(3)To balance a chemical equation, you change the atoms in front of each substance until there are the same number of each type of atoms in both reactants and products

Alka-seltzer Lab

Hypothesis: If we are to put alka-seltzer in varying degrees of water, then the higher heat will make the alka-seltzer dissolve quicker.

Results: After testing we found that our hypothesis was proven during this experiment. We tested the alka- seltzer at 2,27, and 51 degrees. At 2 degrees it took 143 seconds to dissolve. At 27 degrees it took 31 seconds. Finally at 51 degrees it took19 seconds for the alka-seltzer to fully dissolve. My group thinks that the reason the alka-seltzer reacted quickly with the hot water is because there was more energy in the hot water so the alka-seltzer is reacting faster. With the cold water there was less energy so the reactions happened slowly.
In the future I would like to see if the temperature of the actual tablet would affect the reaction as drastically as the temperature of the water did. I would also like to see if there was some sort of chemical we could add that would stop the alka-seltzer reacting. During the experiment I would also like to see what it looks like on a smaller scale and see smaller clusters of atoms reacting.

Freezing- Boiling Lab

Hypothesis: If we freeze than melt  water than it will have a freezing point of around 0 degrees celsius and melting point of around 15 degrees celsius

Results: After testing this is the graph that the logger pro software gave us.

As you can tell by the graph we never got the desired flat line that was supposed to come toward the end of the graph.  For the freezing water or the red line we think this may have been because we didn’t have the test tube submerged enough until the last minute and a half  when the temperature actually started going down. In the end we couldn’t figure out the exact freezing point for water but we think it was somewhere around -5 degrees celsius where it was at the end. We ran into the same problem with the melting point. We got the ice to melt and spike but we never got the desired flat line to give us the exact melting point. The results were flawed but we think the freezing point would be around -1 degrees Celsius and the melting point might be around 10 degrees Celsius.




1. What happened to the water temperature during freezing? During melting?
During the freezing the temperature went down and flat at 0 degrees. When melting the temperature goes up quickly but we didn’t get the flat line we needed.

2. According to your data and graph, what is the freezing temperature of water? The melting temperature? Express your answers to the nearest 0.1°C.

According to our data our freezing point is 0.5 degrees and melting as 10.6 degrees celsius

3. How does the freezing temperature of water compare to its melting temperature?

The freezing temperature is lower because the less energy  means less heat.

4. Tell if the kinetic energy of the water in the test tube increases, decreases, or remains the same in each of these time segments during the experiment.
a. when the temperature is changing at the beginning and end of Part I b. when the temperature remains constant in Part I c. when the temperature is changing at the beginning and end of Part II d. when the temperature remains constant in Part II
a) In part 1 kinetic energy decreases and b)then is pretty gradual after that point because the energy is the same for a while. In Part 2 c) it changes because the ice melts and the water enters the test tube. d) It remains constant because it is at room temperature.

5. In those parts of Question 4 in which there was no kinetic energy change, tell if potential energy increased or decreased.
It decreased because water loses energy if it is not being affected. There is gradual loss in energy over time.