Wednesday, March 23, 2011

Yeast Beasts in Action Lab Investigation

Today, we worked on a lab that would test the pressure of different solutions and yeast. The three solutions that we tested were an acid (Diet Coke), A Neutral (Milk), and a Base (Stomach Antacid). My hypothesis was that the most acidic would react the most, my hypothesis was incorrect. The yeast reacted most with the base. I think that this is because the two reactants are more reactive together than with any other mixture. Here are some pictures of the investigation:




There were some questions involved in the lab and here they are:
1) In which mixture was the yeast activity greatest? A: The most basic of the mixtures.
2) In which mixture was the yeast activity least? A: The most neutral of the mixtures.
3) What can you conclude from the results of your experiment? A: I can conclude that basic mixtures are the most reactive with yeast.

Thursday, March 17, 2011

Conservation of Mass Lab Investigation

Today we did two experiments, one with Pop Rocks and soda and one with the cliche vinegar and baking soda. I predicted that if we put Pop Rocks in a soda bottle, then the balloon at the top would almost fill with the gas. I was partially correct because the balloon was partially filled but only like half full. I then predicted the same for the vinegar and baking soda and I was correct, out of a 9" balloon, about 8.5" were full of the carbon dioxide. The things that went wrong, oh don't get me started. First the Pop Rocks would get stuck when we were trying to put them in the balloon. Next, the Pop Rocks did not dissolve all the way which produced not enough gas, or so we think, the balloon also leaked the gas all over the place, good thing that it isn't toxic (or maybe it is, in high enough quantities). Then, the balloon that was for the vinegar and Baking Soda experiment got a giant hole in the side so we had to redo that experiment. Then the balloons just leaked the gas so it went from a full balloon for the vinegar experiment to a half full balloon. At least we tried the experiment.

Tuesday, March 15, 2011

Chemical Reactions and Temperature Lab Investigation

Today we decided to find out if temperature would affect the reaction time of of alka-seltzer and water. My question is: What happens to a chemical when you add or take away heat? My hypothesis is: If we heat up a chemical reaction, then it will speed up the reaction. Here is my data:
Room Temperature Water: Used 266mL of water, started at 23.9ºC and ended at 23.6ºC while taking 39 seconds for the reaction to occur.
Cold water: Used 133mL of water, started at 2.1ºC and ended at 3.2ºC while taking 2 minutes for the reaction to occur.
Hot water: Used 266mL of water, started at 50ºC and ended at 48.6ºC while taking 23 seconds for the reaction to occur.


A Graph of the reaction times and the temperatures
I accepted my hypothesis because by making the reaction hotter, it sped up the reaction.

Friday, March 11, 2011

ChemThink Chemical Reactions

Each comma separates answers for each blank
1. Reactants
2. Products
3. Chemical Reaction
4. Changing
5. Breaking, Forming
6. Materials
7. New, Less
8. Create a change
9. 2, 1, the, 1
10. H: 4 atoms in reactants, 2 atoms in the products, O: 2 atoms in the reactants, 1 atom in the products.
11. A balanced reaction
12. elements, atoms
13. 3,1,3
14. 1,1,1,1
15. 2, 2
16. O, Cu, Cu
17. 3,1,3
18. 1,2,2,1
19. 1,3,2
20. 2,2,6
21. 4,6,4,6

Summary:
1. A change in chemical bonds of atoms.
2. Present before and after the chemical reactions.
3. Number, atoms

Wednesday, March 9, 2011

Polymer Lab Group Investigation

Yesterday, we took our results from last weeks labs and came up with a lab that we wanted to do by ourselves and we decided that we would add or subtract some borax solution to the glue experiment to see what it did. I thought that if we added some Borax then the polymer would be stretchy and very bouncy. The polymer was very bouncy but did not stretch very far. The control was in the middle of the polymer that we took borax solution from. The polymer that we took the borax solution from was very stretchy but only bounced seven centimeters. While we were making the third polymer, it started to look like sour milk. For trial two (control) we used 25 milliliters of borax solution, we did that exact experiment last week but did not test the stretch. For trial two we used 35 milliliters of borax solution, it was the bounciest but did not stretch very far. For trial three we used 15 milliliters of borax solution, it did not bounce very high but it stretched 60 centimeters.

Thursday, March 3, 2011

Sodium Silicate Polymer Lab Investigation

Today and Tuesday, we worked on creating polymers, Tuesday's was with glue and Borax, Today's was with Sodium Silicate and Ethyl Alcohol. We were also given some questions to answer and were told to tell you guys our results. We tested the polymer we made today and Tuesday for bounciness (or a rebound test) at room temperature and at a cold temperature and here are our results: Tuesday's room temperature rebound test: 6cm., Tuesday's cold rebound test: 5-9 cm., Today's room temperature rebound test: 16-19cm., Today's cold rebound test: 10-15 cm. The cold rebound test was shorter on both counts. Our biggest problem today was our polymer falling apart as I was trying to make it into a ball for the rebound test, I fixed this by drowning it in water and somehow it became super-mutable again and i became a ball after that. I thought that if you add ethyl alcohol to a sodium silicate solution, then it will make a polymer. I was correct that it would make a polymer but not eh kind I thought it would. I thought that it would make a sort of mutable polymer. But, the polymer that it did make was a very solid and immutable substance.

1) What characteristics are similar between the two types of polymers and what are the differences? The similarities are that both polymers were bouncy and white, and both were essentially solid. The differences were that Tuesday's polymer was still kind of mutable, today's polymer was completely solid.

2)Most commercial polymers are carbon based. What similar properties do carbon and silicon share that may contribute to their abilities to polymerize? They both have four electrons in their outer shells that may allow them to link together very closely with other things to make a polymer.

3) Plastics are made of organic (carbon based) polymers. What similarities does silicone polymer share with plastics? Silicon has the ability to replace plastic because they both can form into any shape you want.

4) How do you know that a chemical reaction had taken place when the two liquids were mixed? I knew because the two substances combined and as soon as the stirring started, the sodium silicate polymer was sticking to the stirring rod.

5) How could you find out what liquid was pressed out of the mass of crumbled solid as you formed the ball? When I rolled the ball, the ball released water. i knew this because my hands got very wet and if you added water to the ball, it allowed the ball to become mutable and when the ball dried out, it was very solid.

6) Compare your ball with those of the other members of the class. How many properties can you compare? When we compared our results to the group behind us, our ball bounced slightly higher and was smaller and lighter.

Monday, February 28, 2011

The science of addiction

In the first section, it talked about the existing reward pathways which release dopamine in the brain when something pleasurable happens to your body. When you smell something good and have not eaten, you are driven to eat. The reward pathways are also drivers to make you do things.

In the second section, it talked about the different kinds of addicting drugs, their affects on the human body, and how they can kill you. The site also had a place where you looked at mouse brains after the affects of the addicting drugs. It also talks about how drugs are addicting adn why they are and the least potent ways to take drugs.