Yeast Beasts In Action: Lab Investigation

In this lab, we tested different mixtures and their reaction and gas pressure with yeast. We had three test tubes, all containing 3ml of hydrogen peroxide, and 3ml of one different one of the following: Soda (acidic), milk (neutral), and water (base). I had said before we had begun the experiment that the acidic mix would have the most pressure. I had thought this because hydrogen peroxide is acidic, and when yeast and that are mixed, and pretty good sized reaction takes place. Lets see if I was right:

Well... I wasn't. I will say it admit it, even though it is tough to do. Here is what actually happened:

In this lab, the coke mix had an end pressure of 104.69, after two minutes. The milk mix had an end pressure of 104.76 after two min

utes, just beating the coke mix. Lastly, the water mix. The water mix had an end pressure 105.09, beating both the soda and milk mixes.

Picture/graph:

*In red you can see the soda mix. Blue is the milk mix, and green is the water mix. This graph shows up to two minutes.

You can see here obviously that the water mix won, but the weird thing here, is the soda mix. It got off to a great start, looking like it was going to have a HUGE amount of pressure, but the it just leveled out. Im not exactly sure why this happened, maybe an error on our part, or maybe it was just supposed to happen like this.

In the end, I definitely rejected my hypothesis. I was actually dead wrong. What I thought would happen was the complete opposite of what really happened.

Conservation of Mass Lab Investigation

In this lab, we used two different mixtures in soda bottles. The first test was mixing soda with pop rocks (known as the exploding candy). The second test was with the pretty cliche vinegar and baking soda, but it still was pretty cool. The point was to see which one let out more gas, the soda mixture or the vinegar mixture by attaching a balloon to the top of the bottle.

My hypothesis was that the two mixtures would obviously fizz, bubble and give off gas. I had also thought that the vinegar/baking soda mix would make the balloon bigger, because it is the most commonly used mixture for volcanoes and experiments like that. If the pop rock mixture worked better, why wouldn't everyone use that? Lets see if I was right:
















*here you can see the first balloon that was pretty good sized, using the soda and pop rocks, but check out this one:















*here you can see how much the vinegar and baking soda is fizzing and making bubbles, and how much more gas went into the balloon, and it wasn't even done yet!

I accepted my hypothesis, the vinegar mixture made a bigger balloon and released more gas, but the pop rock mix did a pretty good job too (plus it tastes a LOT better). The vinegar mix balloon also filled grew much faster, which just adds to the fact that it is the ideal choice for volcano experiments and such.

Chemical Reactions and Heat Lab

In this lab we were testing how fast an alka-seltzer would dissolve in heated, room temperature, and cold water. I had thought at the beginning that the hotter the water was, that faster the water would dissolve... lets see if I was right:

In our first test we used the hot water. We used a hot plate to get the temperature of to 50 degrees Celsius, then dropped in the alka-seltzer. We saw insta

nt bubbling as the chemical reaction started. The bubbling continued for 22.98 seconds until the alka-seltzer dissolved completely.

In our second test, we used room temperature water. The temperature was 26.1 degrees Celsius when we dropped in the alka-seltzer. The bubbling this time lasted 35.06 seconds, over 10 seconds longer than the first test.,

In our last test, we used cold water. We accomplished this by placing in the water, and stirring in for a minute, just to be sure the temperature was even. The temperature this time was 3.6 degrees Celsius. After the alka-seltzer was dropped in, it took a whole minute and 41 second to dissolve (1:41.81 seconds)! A funny thing happened this time though. Before the alka-seltzer was dropped in, the

temperature was at 3.6 degrees, but after it was dropped in, the temperature dropped over a full degree, to 2.3 degrees Celsius. A 1.3 degree change. The only thing that changed in between this drop in temperature was the alka-seltzer being introduced. I think the change in temperature had to do with the bubbles, because the alka-seltzer itself was not chilled.

Diagram of results:

*Here you can see how much time in took for the frozen (top) to the heated (bottom), and how much of a difference there was between the times.

Picture of reaction:

*Here you can see the very end of the reaction, right as the alka-seltzer completely dissolved. This test was the chilled test with the ice inside.

In the end, I accepted my hypothesis. The alka-seltzer took longer to dissolve as the temperature went down. I'm not exactly sure why this happened, but I think it has to do with the melting and freezing that comes with heating and cooling, and how it affected the alka-seltzer.

Chemthink Questions

Answers to questions:

1. Reactants are the starting point for a reaction.

2. The ending materials in a chemical reaction are called products.

3. The arrow indicates the change of the chemical reaction from the start to finish.

4. Rearrangement.

5. Breaking, Forming.

6. Atoms.

7. Missing atoms, New atoms.

8. Rearrange the bonds.

9. 2, 2, 1, 1.

10. 2, 1, 2.

4 hydrogen atoms 4 hydrogen atoms

2 oxygen atoms 2 oxygen atoms

11. The law of conservation of mass.

12. Atoms, Mass.

13. 1, 1, 2.

14. Cu atoms - 1 Cu atoms- 1

O atoms - 2 O atoms - 1

15. Same number of O atoms, O.

16. Cu, O2, Cu

17. 2, 1, 2.

Cu - 2 Cu-2

O-2 O-2

18. 1, 2, 2, 1

19. 1, 3, 2.

20. 2, 2, 3

21. 4, 3, 2.

Summary:

1. Breaking bonds, making bonds, or both.

2. The atoms must be present before and after the chemical reaction.

3. Coefficients, atom.

Polymer Lab Group Investigation

My group decided to take a different spin on the original polymer lab we had done with the Elmer's Glue and the Borax. The way we changed this lab, was by making two different polymers, one with 50 percent more glue (60ml), and one with 50 percent less glue (20ml) than the original amount (40ml). The problem her was, the polymer became saturated, so unfortunately, the smaller amount of glue made no difference due to it not absorbing all of the borax. We decided to just test the polymer with more glue, due to there being a different mixture with more glue and absorbing more borax.

To stay consistent, we still used a quarter sized ball, and tested the rebound... here are the results: The original ball we made had bounced an average of 14.8cm per bounce. When more glue was involved, the ball bounced a considerable difference of 2.7cm, being at an average 17.5cm. Also, when chilled, the ball improved another .3cm than when room temperature, although the ball bounced inconsistent, probably due to the oddly shaped ball from sitting in the fridge for ten minutes.

What we pulled from this experiment was that with more glue involved, the polymer felt more solid, which probably made the ideal "bouncy ball" that obviously made it bounce higher than before. Also, when chilled, the ball became slightly more solid, which also probably helped the rebound of the polymer.

Here you can see the bigger polymer (60ml glue) to the right already formed and in ball shape, and the smaller polymer (20ml glue) still being formed to the left.

Sodium Silicate Polymer Lab Investigation

Sodium Silicate Polymer Lab

The point of this lab was to find out what kind of polymer can be made from Sodium Silicate and Ethyl Alcohol, and if it will bounce higher than the polymer made from Elmers Glue.

My hypothesis, before this lab had begun, was: The Elmers glue polymer would have the

greater rebound than the Sodium Silicate polymer, due to the glue being thicker than the silicate, and that the room temperature polymer will bounce higher than the chilled polymer. Lets see if I was correct.

After the two liquids were mixed, the mixture took the qualities of a solid very fast. After the solid was created, we molded a ball out of the solid (which took some work, due to the constant crumbling). Once a nicely shaped sphere was created, we got ready to test the rebound.

At room temperature, we tested the rebound 10 times. The 10 trials came out to an average of 25.8cm per bounce, almost twice as high as the rebound of the glue polymer.

We then placed the polymer in the fridge for a chilly 10 minutes, then took it out. We then tried the same exact test of 10 bounces, and this time, while chilled, the ball bounced an average 22.4cm, per bounce. This means that the room temperature polymer and the chilled polymer rebounds had a difference of 3.4cm.

The polymer felt mostly hard, but had a little bit of squishiness to it. It smelled like the ethyl alcohol, and looked like it was made out of a shiny, granite like substance.

Image 1:

Here is an image of the two liquids being mixed, and if you look closely, you can start to see a solid being formed.

Image 2:

This is an image of the polymer after the liquids completely creating the solid, and after a lot of hard work turning it into a sphere like shape.

I did NOT accept my hypothesis. In fact, I was completely wrong. The polymer we made today bounced almost twice as high as the glue polymer! So I was a little bit off to say the least. No errors occurred during this lab.

Questions and Answers:

What characteristics are similar between your two types of polymers you have made? Differences?

The polymer made with glue was much more malleable than the one made from the silicate. Also, the glue one was white, and the silicate one was almost crystal like. One the other side, the both had a pretty good rebound, even if the silicate polymer bounced much higher.

Most commercial polymers are carbon based. What similar properties to silicon and carbon share that may contribute to their abilities to polymerize?

They each had 4 chemical bonds.

Plastics are made of organic (carbon based) polymers. What similarity does the the silicone polymer share with the plastics?

They are both hard, but can still be molded.

How did you know that a chemical reaction had taken place when the when the two liquids where mixed?
Instantly, the two liquids started to form a solid, so I knew the chemical reaction was taking place.

How could you find out what liquid was pressed out of the mass of crumbled solid as you formed the ball?
You could absorb the liquids that were pressed out, and test what that certain liquid was.

Compare your ball with those of the other members of class. How many properties can you compare?

Spherical, same color, smell, feel, and everything else, since it was made out of the same materials. The only thing that differed from time to time was the size and shape.

The Science behind Addiction

The Natural Reward System for the Brain

Neurons are cells directly responsible for passing chemical and electrical signals down and along the pathways of the brain, and each neuron has special functions like storing memory and/or controlling our muscles.

In the center of the brain lies the reward pathway, which drives our feelings of motivation, behavior and reward.

Drugs Alter the Brains Reward Pathway

Drugs bypass the five senses and directly enter and activate the brain's reward circuitry, this is how drugs can cause a quick jolt of pleasure. The abuse of drugs can affect the brain in such a huge way that the brain will start to try to adapt. One way the brain adapts is to lower the number of dopamine receptors at the synapse, this will lead to the user needing more of the drug the next time they want to get high.

As the brain continues to get used to the presence of the drug, areas outside of the reward pathway will also start to be affected. Brain regions that are used for things like learning judgement and memory can start to physically change. Once this happens, drug seeking behavior becomes a very hard to break habit, which in turn leads to the so called "Drug Addict". Drugs can affect the brain and the body so much that an overly large dose can actually kill the person using the drug.