Yeast Beasts in Action Investigation

So we first took hydrogen peroxide and poured 3mL of it into a graduated cylinder and then poured 3mL of it into the three test tubes we had. After we poured the hydrogen peroxide into the tubes we took three different mixtures into the tubes. Those mixtures were Diet Coke, Skim Milk, and a stomach antacid. We poured 3mL of those three solutions into their test tubes, which were marked acid, neutral, and base. After all the mixtures were poured into their tubes we had to get 50mL of water and pour it into our beaker. We then added half a teaspoon of yeast into the beaker, to make a yeast solution. We then added two drops of the mixture into one of the tubes and measured the gas pressure. We then repeated the process for the other two tubes. We used logger lite to measure the gas pressures. There was a gas tube that was used to measure to pressurized gas. The measurements for the first tube pressures are in the picture below.

The pressure measurements for the second test tube are in the picture below.

The measurements for the third are below.

As you can see by the pictures each measurement is much different. Some are higher and some are lower in their pressure levels. The pictures go in the order of acid, neutral, and base. The base ended with the most and the neutral ended with the least amount.

Conservation of Mass Lab Investigation

The first lab that we did was the pop rocks one. We went through all the procedures and started the lab. We poured pop rocks into a balloon and put that balloon over the top of a 20oz soda bottle. Our soda happened to be Sprite. We attached the balloon to the lid and poured the pop rocks in. The reaction didn't start for about 2-3 minutes after the pop rocks fell into the soda. After a few minutes the balloon started to fill with gas. It started to blow itself up. It ended up maybe about 3 or 4 inches tall and about 1 1\2-2 inches wide. The overall process of the gas into the balloon seemed very slow compared to other groups. Our balloon also seemed a few inches smaller than all the other groups balloons. That could have had to do with the type of soda because almost every group had a different soda type. If our soda was a type of cola maybe the balloon would have been filled more with the gases. Also to make the balloon fill with more gases we tried to shake the bottle and the balloon grew maybe a half an inch or maybe a full inch larger.

After the first lab we had to wash out our soda because our empty bottle had a lid to big so the balloon wouldn't fit over it. In this lab we had to take 50mL of vinegar and pour it into a bottle. Next we poured a half a teaspoon of baking soda into a balloon which we then put over the bottles lid. The reaction only took maybe 15-20 seconds. The gases went into the balloons must like the pop rocks lab. There seemed to be more gases coming out because the balloon was much bigger. Although our balloon may have been bigger, but we couldn't get it to hold so we lost an average amount of the gases so that could have been a variable in the size of the balloon. Another possible variable could be that we had to use the same bottle for both labs. There still could have been small amounts of pop rocks in the bottle that may have interfered with the lab itself. I also realized that still other groups had much bigger balloons. We were not sure how they got them like that. We tried the shaking process like in the last lab, but it had no affect on the balloon at all. Other groups may have had more success with the shaking then us.

Chemical Reactions Temperature Investigation

We did the room temperature experiment first. We measured out 266mL of water. We then put in the temperature probe into the water. The temperature started at 23.1 degrees C. We ran a test for a minute and the temperature stayed the same. After we dropped the tablet in we timed it until the reaction had stopped. The temperature dropped from 23.1 to 22.7 degrees C. The next test we did was the hot plate one. We took 266mL of water into a beaker. We then put the beaker of water on the hot plate and we timed and took the temperature. We had to wait until it got to 50 degrees C. It took about 3 minutes to get to that temperature. We then took it off the hot plate and dropped the alka seltzer tablet in it and recorded the data. It took about 28 seconds for the reaction to stop. The temperature dropped about 2 degrees C. The third test we did was the cold test. We measured out 133mL of water and put 2-3 ice cubes in it. We then put in the temperature probe and stirred the water for 1 minute. The temperature started at 0.6 degrees C and ended at 0.3 degrees C.

ChemThink; Chemical Reactions

1. reactants

2. products

3. chemical change has happened

4. rearrangement of bonds

5. breaking and forming

6. same atoms

7. missing or new

8. rearrange the bonds

9. 2,1,1,1

a. hydrogen and oxygen

b. 4 and 2

10.

11. Law of Conservation of Mass

12. atoms and masses

13. 2, 1, 2CuO

14. 1,2 and 2,2

15. 1, oxygen

16. oxygen, Cu, Cu

17. 2,2,2,2

18. 1,2,2,1

19. 1,3,2

20. 2,2,3

21. 4,3,2

Summary

1. Breaking old bonds and forming new bonds.

2. All of the same atoms and thus the same mass before and after a reaction.

3. Coefficients and atoms.

Polymer Lab Group Investigation

In this lab we added cornstarch to the borax lab that we did last week. We added less water and less glue to the solution. We only used about 2 tablespoons of the borax solution. We added the cornstarch after we added the small amount of water to the glue. Once we started to stir all the materials together it started to get harder to stir. It became a very sticky and white solid goop. It seemed like we took the inside of a marshmallow and out it in our hands. It was almost impossible to mold together into a ball. It would just stick to our palms and fingers. After a couple of minutes we noticed that the solid became less sticky and was finally able to mold into a small ball. The ball was not able to bounce it would just flop down and do nothing. There was no roll or any rebound. After a little more time of kneading it in our hands it started to be more elastic and it bounced up maybe about 2 or 3cm. It was definitely elastic enough to stretch about 2 feet or maybe 1 and 1/2 feet. We decided to break it into two different pieces and stick one in the fridge for about 10 minutes or so. During that period of time we still just kept kneading the ball hoping to get some sort of reaction so that the ball will be able to bounce and become much less sticky, but we had no success with it. Once the 10 minutes were up we got the other ball out of the fridge and it look like a partially deflated ballon. I pulled it out and it stuck to the surface and I had to peel it off. We took it back to the table and it was very sticky and cold. It also wouldn't bounce. We compared the elasticity of the two. They both stretched to a large length, but the one that was in the fridge seemed to be able to hold it more together and stretch farther then the other one that was being rolled the whole time. I think that if we did this same lab again with the same materials we should increase the amount of everything because we only used maybe about a tsp of water which was not enough if you ask me. I think that we should at least double or even triple the amount of materials. Also when we put the borax into the water it seemed to have a very hard time dissolving into the water. We stirred it for several minutes but almost all of it didn't dissolve. That could have been a huge factor in the characteristics of the solid. Maybe if the borax had dissolved more into the water the ball wouldn't have been as sticky as it was and maybe a little more bouncy and easier to stick together into a solid material. If the material wasn't so sticky I think it definitely could have bounced at least 2 or 3 more cm than what it did. This was a good lab because we were able to make a solid out of those same materials but just adding a small amount of cornstarch to the solution.

Sodium Silicate Polymer Lab

I thought that when the two chemicals were combined it would make a solid. Once we combined the two it became a solid once it was stirred. Sodium silicate and ethyl alcohol were mixed and then stirred they became a snow-like substance. It was a crumbly white solid that seemed very much like snow. It was only about the size of a nickel. It would crumble if tried to roll in a ball, but once you rinsed it under water and then tried to form it into a ball it was much easier and it stuck together in a ball. Just like for the borax polymer we did a rebound test from 30 cm. When the ball was bounced it bounced either a little more or a little less than 15 cm. Once we dropped it about 5 or 6 times we put it into a refrigerator for about 12 minutes. Once we took it out it was much colder than it was before. We did the same rebound test from the same height. It bounced about 10 cm. So it was an obvious change in height, which can prove that temperature change can affect the rebound test for polymers that have been tested with a rebound test from the same height. It was strange to see how two liquids can form a solid when mixed together. It makes me wonder what other chemicals can be combined to make a type of solid. I think that if we increased the amount of the two liquids, that it would make a larger, thicker ball to work with. If we could try that I think that the ball would bounce higher if dropped from 30 cm. If you were to use say double or triple the amount of liquid what would the differences be between the regular amount and the increased amount.

Our ball was differed in size from other people in the class. Some were much bigger and some were much smaller. There were some that were more crumbly than others. I think that would all have to do with the amounts of silicate and ethyl alcohol and the care that was put in to it. Some people could of had more success in combining the ball when stirring so more pieces stuck to it instead of there being lots of little chunks in the beaker. If it was stirred fast or slow may be a variable in that part of the lab.

The Science of Addiction

There are many different drugs that affect the brain pathways in many different ways. All are damaging to the brain. Most of the drugs have a chemical that will go into the brain pathways and release and excessive amount of dopamine and it doesn't let it stop. They will block the exits for dopamine, so that the person will remain happy and like to use these drugs because they like the happy sensation when they are using them. Many of the drugs are highly addictive and do more damage over time. For example cigarettes have nicotine in them which is a chemical that causes the brain to want that chemical. That is why many people smoke, because once they start the brain sends signals to the body saying that they want this and the feeling is so strong that people have to smoke a cigarette or else they can have terrible lose of nicotine in their body and freak out. All drugs will trick the brain into wanting more. Any one who does drugs may want to quit but can't because of their addictive force.