So here's the general idea of organic chemistry, which is also the largest and most organized branch of chemistry. Carbon, because of its ability to make 4 strong bonds, is the underlying structure and foundation of most compounds. Hydrocarbons are the simplest examples. We reviewed the first 10 hydrocarbons in class again: methane, ethane, propane, butane, pentane, hexane, heptane, octane, nonane, and decane. But before, we had only gone as far as drawing their Lewis structures and their 3-D models. Now we got to actually make the compounds using organic chemistry kits. Through these kits, we learned about structural isomers, compounds with the same formula but different arrangments of atoms and thus different properties. We learned how to name each of the compounds that we made and even listed all 18 isomers of octane. The next day, we advanced even farther by making alcohols and ethers, which is a combination of 2 alcohol groups.But what I enjoyed most out of these couple of days spent on Organic Chemistry was the Extreme Oreo Makeover Video. This video created by '09 alumni featured a film on the history of oreos. When it was first invented in February 1912, everybody loved to eat oreos because then, people believed that trans fat was healthier than saturated fat. After 1944, trans fat was discovered to be bad for the human body, even though it increases shelf life and flavor stability. Eventually, the oreo had to go through an extreme oreo makeover. Overall, this video was very amusing and fun to watch, and even though it may seem like an old film created simply for entertainment, "it really did teach us about many different aspects of nutrtion."
June 5, 2010
Give me a C! Two for One and Two for All!
The Horrors and Joys of the Unit 7 Exam
...Only it wasn't.
Sayoni Saha, period 7, had mixed opinions. "I studied very hard, but didn't do well. Well, compared to others, I did okay, but I didn't do great. Mr. Bender said the test for period 7 was harder, and I think it was because we had less recycled questions. So I think I didn't do so well because the test was hard... I did all the pHs and used all the CHIPs to study, but I should have studied more comprehensively. I focused more on some stuff and on test, I didn't know how to do the problems which I didn't study for so well."
Catherine Qian regrets not having studied so much. She said, "I did badly. I really wish I had studied the pHs. When I was taking the test, I really felt that I would have done so much better if I had done all the pHs. It would also have helped me understand all the material in class too."
CST seemed to have helped students. Borah Lim, period 3, when taking the test, felt very confident because she had gone to CST. It helped her with a lot of material she had previously been confused about and was glad she had the opportunity to go. When taking the test, she felt calm because she understood all the material.
Michelle Lee, period 7, struggled through the exam. "I was my fault. I got confused in class and then didn't study, which was stupid. I really should have studied. I though the test was easy for those who knew the material, but I did really badly."
One student felt that she did badly because he had so little time before the test. "I did really badly. I tried to study, but I was really busy with my cpr. Well, Mr. Bender said it was hard, so that might also be a part of it. But I didn't do any of the pHs, which was really stupid. I should have done them. I was really busy last month, well this month too. I didn't go to cst, though I usually do."
I personally did not do too well on the test because I was confused on some really simple things that I thought I understood. As luck would have it, I messed up on the test ): The Unit 7 Exam didn't go down so well with many students--let's hope that they get their act together before their next quiz.
7 days. Pass it on.
- In July 2009, biofuels production was banned in CA because of safety reasons with the storage of pure biofuels. =/
- Ethanol may be an ALTERNATIVE FUEL, but it has its pros (safer, has same amount of CO2 emission as regular fuels) and cons (takes away corn supply, energy production is not efficient)
- Biofuels - made from oils and fats used for vehicles that run on diesel only; its the greener choice because it helps reduce air pollutants like carbon monoxide, hydrocarbons, and sulfur oxide.
- What's the future of biofuels? Much research is going on to see if biofuels really is a potential fuel alternative. Even though its production has tripled (4.8 billion gallons in 2000 to 16 billion gallons in 2007), today, it still accounts for less than 3% of the world's transportaion fuel supply.
This CPR video was one of the most interesting CPR presentations we've had this year. Many people agree that because the didactic film kept us students at the edge of our seats waiting to hear what would happen next, we became more interested in biolfuels. In addition, we learned more about potential sources of energy in the future that could be helpful to our environment, such as ethanol, biodiesel, and algae, which was the most interesting to me. Before, to me, algae was a plant that I learned about in Biology Honors last year. However, now, I know that algae can be another potential energy source because not only does it consume carbon dioxide as food, which would be a huge plus to our planet, its production and growth is also easier because it takes up less space. Overall, this was a fresh, funny, and suspenseful "breath of biofuels".
Sad Cornless Milley
How is corn being made into ethanol fuel? Unfortunately, it's not as simple as sticking a gas pump into an ear of corn. There are 12 essential steps in the process.
1. Delivery of corn to the storage.
2. The corn is stored until ready to be processed.
3. Corn is made into flour.
4. Water and an enzyme are added to the flour to make a paste.
5. The paste is watered down.
6. Yeast is added.
7. Distillation to separate the stillage and the alcohol.
8. Dehydration to turn 190 proof into 200 proof.
9. Storage and transportation to be mixed with gasoline.
10. Seperating heavy solids and fluids.
11. Drying of solid
12. Collection of carbon dioxide for further marketing.
And then, ta-da! The E-85 that we can buy at pumps.
So if oil is a nonrenewable resource, and ethanol is, why don't we use it all the time? Well for one, to grow enough corn to support the entire United States with pure ethanol would require 97% of the arable land in the nation. That leaves about 3% to grow food and raise livestock. There is also the argument (and Milley's plight) that we should not take food away to make gas for our cars. However, it is widely used in some areas (most noticeable in the midwest).
When Mr. Bender visited, he saw many signs that declared certain corn fields for ethanol.
So the Poor Hungry Children of America explored other possibilities of renewable resources.
1. Biohydrogen: It can fuel without carbon dioxide emissions. Made from bacteria releasing H2. However, very expensive to create and inefficient.
2. Biogases: Contains methanol and landfill gas.
3. Bio methanol: Methanol made from biomass, which is a renewable resource. But it's very expensive because it requires so much biomass to produce only a little bio methanol.
4. Biodiesel: Already in use, it is made from oils or fats, even leftovers like from fryers at fast food restaurants! We do not need to modify our cars to use biodiesel.
5. Algae fuel: It is made by feeding excess CO2 to algae, then starving them. The algae breaks open, releasing oil. This is an efficient method because algae create lots of oil in a little amount of space.
Alternative fuels have come a long way. Will ethanol remain a prominent member of the club?
So much heat from such a little atom!
What do we think of when we think of nuclear? Radiation, explosion, bomb... all the stereotypical cons of nuclear power. Mr. Bender showed us a few clips concerning nuclear power and bombs: The Simpsons (in which a person glows very brightly due to continued exposure to nuclear power), The Sum of All Fears, and a clip from Indiana Jones (in which Indiana hides in a lead lined fridge to save himself from a nuclear bomb). Later in class, we learned of some of the pros of nuclear power and how helpful is could be, as is exemplified by the power plant in New York.
We viewed newspaper articles in class. One of the articles was about Iran, and their new uranium enriching machine. Iran can now process uranium faster, which means they'll have lots more uranium-235 on their hands. This was the cause of much commotion and protests from other nations, as this will make creating nuclear power that much easier for Iran ):
So what makes nuclear power so powerful?
It had all to do with heat, with the nuclear binding energy (NBE).
And the famous equation E=mc^2.
m=mass
c=3.0x10^8
When the electrons, protons, and neutrons do not add up to mass of an atom, the mass deficit has been used as NBE. To calculate the NBE, you need only to plug in the mass deficit into the eqaution E=mc^2. Because c is such a great number, the tiniest mass losses can result in huge releases of energy.
Happy fish, dead fish, BEEEES!
Alpha decay, whose product isotope is called the daughter, can be blocked by paper. This process resembles a nucleus "coughing up" helium nucleus.
Lazy shoelike electrons like to play monopoly!
Electrons are like shoes, they come in pairs. In each level, there is a maximum is two electrons. When the energy level is filled with two electrons, the electrons have opposite spins and are denoted by up arrows and down arrows.
Electrons like to "play monopoly". It is always singles first! They only pair up when necessary.
The first level is 1s, and includes Hydrogen and Helium and the second level is 2s. These are both spherical. The third level is 2p, and 2p has three different orbitals. 2Px, 2Py, and 2Pz. 3d, the fifth level, had five different orbitals.
To help us understand, Mr. Bender showed us an oh so wonderful video from the World of Chemistry where Don is a coach for the Electron Team Baseball. He showed us how electron configurations worked physically, using benches and baseball players to act as levels and electrons.
A rather simple and easy concept, compared to some of the pretty complicated things we learned this unit!
HUP HUP HURRAY!!
In Jurassic Park: The Lost World, one of the main characters, in the middle of a jungle searching for dinosaurs, states that dinosaurs behave differently when they know that they are being watched. This amazingly related to how the electrons in atoms can't be "watched" because while we are shining radar right on them, the radar is changing their actions and speed.
Watching the clip from the beginning of Star Trek was even more exciting. At first I didn't understand why Mr. Bender would be showing us a extremely entertaining scene of a Robocop chasing James Kirk speeding in a car in class, but later I realized that the point he was trying to bring up was that James could have been speeding because the Robocop had used his radar gun on him. Of course, the radar gun was not to blame, seeing as the car's weight is much too large to be affected by a radar gun. Heisenberg Uncertainty Principle works for electrons, which have small masses. HUP stated that it's impossible to know the position and momentum of electrons at the same time. Even though I don't fully comprehend how this principle works, let alone imagine how in the world science advanced so far as to allow people to see microscopic particles, I guess "it's all about the electrons"!
Rainbow Sripes!
As human beings, we can only see from 400 nanometers to 700 nanometers. Anything after or before that is not visible to the human eye. At first, we had a little difficulty using them, as we did not know exactly know what we were looking for. Mr. Bender cleared that up pretty soon, when he realized some of us were confused. But after that, we started noticing all these random lines and dark spaces....
So what causes the jerky rainbow? These brights lines or stripes are called spectral lines, and they exist because energy in light drops in quantums (discovered by Max Planck ). A quantum is a tiny packet of electric charge and light in an atom. When losing or gaining energy, an atom must gain or lose an entire quantum of energy. And results from each of these jumps or drops in a bright stripe, which we can see! Any jump or drop too high goes into the UV range, and we can't see those.
Who gets credit for doing the work? Well Bohr, a Danish physicist in the 20th century, did a lot of the work. He calculated and did the work involved in figuring out the energies in a quantum, but there is a slight issue: his work was only true for Hydrogen! However, his contribution is still great and he gave us a lot of work with. Bohr said that electrons can only occupy certain orbits at certain energy levels, and that electrons have special "allowed" energies. Energy is only absorbed or emitted to move an electron from one "allowed" energy state to another.
Lights, Lights, Lights!
radio micro infrared red orange yellow green blue indigo violet ultraviolet X-rays Gamma rays
(The higher the energy, the shorter the wavelengths and the higher the frequency)
In addition we were introduced to Nehemiah's Bagel Story, which was about a boy who always carried around a specific number of bagels. However, when given some more bagels, sometimes he would refuse, but other times, he would accept. And then later on, he would drop a specific number of bagels. This story explained how lights worked. Nehemiah was Neon, his bagels symbolized energy, and the pile of bagels dropped represented the spectrums that light emits.
Two days after being first introduced to this unit, Bender-led his first Power Point Lecture in Chemistry Honors class to give us a feel for what AP Chemistry is like. This light lecture was very integrated and taught us much new information. Here's a list of the main points.
- Planck's constant! (E=hv) Max Planck proposed that energy comes in packets called quanta
- Einstein used Quantum Theory to explain the Photoelectric Effect
- Bohr - discovered Hydrogen's secret code using Planck's theory; mathematically discovered how to find the wavelenghts of the spectrum we can see for hydrogen
- Bohr's main contributions: electrons can only have certain quantum of energy, which are involved in change of energy levels
- Every element has its own spectrum!
- Thomas Edison didn't invent the lightbulb! He invented the carbon filament that burned for 40 hrs, and he also improved it to last 1200 hrs in 1880
- Incandescent lights - Argon(Ar) and Tungsten(W). Relatively low lifespan because W vaporizes away from filaments, and the filaments then break
- Fluorescent lights - Argon(Ar) and Mercury (Hg). Here's how it works: Ar and Hg gas are excited by electrivity. The electrons calm down and emit UV radiation and some visible light spectrum. Then, the phosphor coating absorbs the UV rays and reemits various parts of the spectrum so that almost all of it is emitted (it's almost white light)
- Incandescent vs. Fluorescent lightbulbs: incandescent - cheaper, safer (no Hg); fluorescent - more energy efficient and isn't 90% heat like incandescent
The response to the Light Lecture was a mixture of reations. Many thought the presentation was interesting and eye-opening to discover things like how EMR plays a tremendously important role in our lives, but I think everyone agrees that it was a very different experience, being taught for the first time through powerpoint. Annie Yau in period 2 said, "The Light Lecture was like an intro to AP Chemistry class, because the whole lecture was powerpoint based, and it was definitely different from what we were used to, but there were some interesting pictures, and it was good practice taking powerpoint notes." Overall, the Light Lecture was a unique and great experience. :)