Wednesday, November 30, 2011

Polymer Lab

Polymer Lab
Question: What will happen if we mix borax, water, and glue?
Hypothesis: I think that they will all combined to create a bouncy ball, or slime like substance.

This picture was taken just after we added everything together to form the picture. As shown, the mixture was quite slimy at this point, and it would stick to your fingers if you touched it. Over time, it began to lose moisture, and it became something similar to play-doh, or clay. In comparison:
Before we added the borax to the glue:
The glue was slimy and and wet.

After we added the borax to the glue:
The glue became hard, and seemed to absorb the borax and water.


Slime Tests
Slime rating: 1 out of 5. Our slime was very slimey at first, but then became less slimey as the time wore on.
Slow poke test: If you shape the slime in a ball, and slowly stick your finger through it, your finger will come out the other end.
Quick poke test: If you shape the slime in a ball, and quickly stick your finger through it, your finger will come out on the other end.
Slow pull test: If you slowly pull the slime apart, the slime forms holes.
Quick pull test: If you quickly pull the slime apart, it will break into 2 pieces.
Blob test: When you roll the slime into a ball, than let it flatten out, it takes about a minute and a half flatten.
Bounce test: If you drop the ball from 30cm above a table, onto a table, it will bounce up roughly a foot and a half.

Questions:
1. How is slime viso-elastic?
It tries to go back to it’s original shape
2. What are the physical properties that change as a result of the addition of sodium borate to elmers glue?
It becomes elastic, regains its shape, bounces, and is much less sticky than plain glue.
3. What would be the effect of adding more sodium borate to your cup?
More sodium borate would have made the slime more compact.
4. How does water affect elasticity of the palmer?
The moisture allows it to be elastic. Elasticity is the object allowing it’s self to be pulled apart.

5. The repeating molecule is
H H
| |
C C
| |
OH H
6 The structural formula of the poly(vinvyl alcohol) monomer circled above ^
C2H3OH
7. Circle the borax cross-linking agent?
The borax cross-linking agent is the B in the center of the two pictures.

When borax solution is added to glue, a certain polymer is formed. That happens when we take multiple monomers, and chemically create a monomer. I would overall, accept my hypothestis, which stated that by adding glue, water and borax, we will create a polymer. If I was to change this test in any way, we should attempt adding more borax, to see if that changes the bonding in any way. We could also try this with adding more water, or glue. Our tests were carried out flawlessly, and our slime was a prime example of what the test should have turned out to be. It was crucial for us that we carry out the test correctly this time, however, A small mistake could have made a big difference.

Kid Zone Polymer Basics

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 ‘links, or mers 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’, ‘phosphorous’, ‘sulfur’, ‘fluorine’, ‘nitrogen’, and ‘silicon’.

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 ‘themal’ 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 & Gibson
Teflon – Discovered in 1938 by Plunkett
Celluoid - Developed in 1869 by Hyatt

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


Plastics have changed the world: Where did the word plastic come from? The word plasticos means ‘to mold‘__It is called this, because plastics are soft and moldable during production.

What are plastics? Define the following words after reading the section titled “What are plastics”

• monomer: monomer is a molecule that contains carbon and other substances. Monomers normally come from oil/petroleum or natural gas. A monomer is a single molecule that is capable of joining with many others, to create a chain of monomers, called a polymer.

• polymer: A polymer is multiple monomers. It’s like a chain of paper clips, the single paper clips are monomers, and when they create a chain they form a polymer.

• organic material: Organic material are things like wood fibers, corn or banana peels.

Polymerization: Polymerization is the chemical process where monomers combined to make polymers.


The steps listed below explain how plastic is made. Fill in the missing blanks.

1. Crude oil, the unprocessed oil that comes out of the ground, contains hundreds of different hydrocarbons, as well as small amounts of other materials. The job of an oil refinery is to separate these materials and also to break down (or "crack) large hydrocarbons into smaller ones.

2. A petrochemical plant receives refined oil containing the small monomers they need and creates polymers through chemical reactions.

3. A plastics factory buys the end products of a petrochemical plant - polymers in the form of resings - introduces additives to modify or obtain desirable properties, then molds or otherwise forms the final plastic products

Polymers are Everywhere: Read the paragraph titled “Polymers are Everywhere”, then answer true or false to the following questions.

True Plastics are polymers, but polymers don't have to be plastics.

False- they are examples of polymers.  Cellulose, the basic component of plant cell wall, and DNA, the long molecule in the nuclei of your cells that carries all the genetic information about you, are both examples of plastics.

True Natural polymers include silk, wool, cotton, wood, and leather.

Thermoplastics & Thermosets: Plastics are classified into two categories according to what happens to them when they're heated to high temperatures. Complete the table below.
Thermoplastics
Thermosets
can it be reshaped? yesno
analogylike ice, when it is heated, it will melt, then you can form it into a new shape. its like a raw egg, it can be a fried egg, you can hard boil it, or scramble it. But once you fry your egg, it can never go back to a raw egg.
strong or weak bondsweakstrong
usesplastic rap, food containers, lighting panels, garden hoses, and plastic bagsspatulas, other kitchen tools, glues, varnishes, and circuit boards.
recycling easy or hard? easy! hard



1. Click the link to make a virtual polymer and choose polyethylene.
A. What type of monomer is used to make this polymer? ‘Ethylene monomers’
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? ‘iniatiator’

2. Click the link to try the matching games.  Record your times or scores in the blanks below.
A. Breakfast Game– 1st Try = ‘9413’   2nd Try = ‘9096’  3rd Try = ‘9399’
B. Polymer Game - – 1st Try = ‘9330’   2nd Try = ‘9313’  3rd Try = ‘9186’

Monday, November 28, 2011

Chem Think; Chemical Reactions

Chemical reactions
  1. Reactants
  2. Products
  3. Chemical change has taken place
  4. There is rearrangement of the bonds
  5. Breaking or forming
  6. Same atoms
  7. Missing atoms or new atoms
  8. Rearrange the bonds
  9. 2 2 1 1
  10. 2 H(2) and 1O(2)--> 1H2O

# of atoms in reactantselement#of atoms in products
4H2
2O1


11. Law of Conservation of Mass
12. Cu atoms and Oxygen atoms
13. 2 Cu+0(2)--> 2CuO
14.
reactantsproducts
Cu atoms= 1Cu atoms= 2
O atoms= 2O atoms= 2


15. 1 Cu atoms,
16. O, Cu, Cu
17. 2 Cu+ 2O---> 2CuO
reactantsproducts
Cu atoms= 2 Cu atoms= 2
O atoms= 2O atoms= 2


18. 1CH(4) + 2O(2)--> 2H(2)O+1CO(2)
atoms in reactantselementatoms in products
1C1
4H2
2O3


19. 1 N(2) + 3H(2)--> 2NH(3)
20. 2 KCIO(3) ---> 2 KCI + 3 O(2)
21. 4 Al + 3 O(2)---> 2 Al(2)O(3)

Summary:
  1. Chemical reactions always involve breaking bonds, making bonds, or both.
  2. The same atoms must be present before and after the reaction.
  3. You change the coefficients in front of each substance until there are the same number of each type of atom in both reactants and products.