Chen,+Yanqi-Tyson


 * 1) Crude oil is a mixture of hydrocarbons that are useless when together. Hydrocarbons are different compounds, or pure substances that have the same molecular composition. Fractional distillation is used to separate the hydrocarbons so that they can be used as different fuels. Basically, the crude oil is placed into a tube, and heat is applied at various intervals and different intensities. Because the hydrocarbons all have different evaporation and condensation points, they can be separated for example by first heating the tube to 150 degrees Celsius until all the gasoline hydrocarbons are removed from the crude oil mixture. Once finished distilling one type of hydrocarbon, the temperature of the tube is increased, thus at the end of distillation, all hydrocarbons will have been separated. The distillation method discussed in the video is very similar to the one discussed in class.

Tyson, Well done! MW

All the way back from Plato’s dialogues about Atlantis, chemical elements have always been able to sneak their way in literature, albeit with different names and altered properties. Plato painted the Temple to Poseidon and Cleito with the fictitious element, Orichalcum, which was most likely inspired by the beauty of gold. In Tolkien’s, //The Hobbit//, the fictional element, mithril, shares many of the same properties as the real element, titanium. Among the properties the two elements share, are that they are both extremely lightweight yet hard, making them a great material for creating armor and weapons, as well, the two elements do not tarnish. Though sometimes fictitious, the various elements that have been used in literature throughout the ages, by definition, could not have been broken down into simpler substances, not even by the monumental temperatures of Mt.Doom.

Tyson, Wow! Great connections! 5 enormous stars. MW


 * Kilogram article**- Since the enlightenment, scientists have worked very hard to set constants/standards to measure the different physical features of the universe. In the SI system, 7 base units were created that would become the basics of all other measurements. The kilogram, however remained the only one that was not completely "perfect" yet, as it still relied on a physical artifact,platinum-iridium alloy, as the universal standard, and not a unvarying physical property of nature. Because the prototype of the kilogram has slowly deteriorated over time, it has now been suggested that a new kilogram be created based on either Planck's constant, or Avogadro's constant, though the change would actually change the actual meaning of Avogadro's constant from a constant to a set value/number. Although quite confusing, the changes will really only impact metrologists.

Tyson, Well, the work of meteorologists affects us all so it's all interconnected. 5 stars. MW


 * Where do Chemical Elements come From-** Elements can be seen all around us, but who would have guessed that they originated in places billions of miles away, in stars. According to the article, when a star explodes, it not only releases great amounts of light, but it also deals out many elements across space. Basically, the elements are formed in the star through fusion due to the incredibly high levels of pressure and heat; everything starts out as simple hydrogen atoms, but eventually other elements such as helium, beryllium, and carbon can be formed as a result of nucleosynthesis, which is basically a form of the "snowball" effect at the atomic level. What happens is that subatomic particles of elements starting with hydrogen are ripped apart and then fused back together to create successively heavier atoms. It was especially interesting to me that neutrons could actually be created through the combination of a proton and an electron. (Makes sense though, as the positive proton charge would cancel out the negative electron charge) This process can be used to create elements up to iron, however the "r" and "s" processes are needed to create the heavier ones. In these processes, extra neutrons are added to the nuclei of atoms. But, that alone could not create heavier elements, as it is the number of **protons** that distinguishes an element**.** Thus, the key lies in beta decay, which is when a neutron splits into a proton and an electron. While this article has provided many answers, and insights to the origin of elements, it also provides grounds for further inquiries such as where the subatomic particles themselves came from.) (Just an extra tid-bit, I actually just recently read an article in //Scientific American,// regarding Planck time and the big bang which further elaborates on the concepts discussed in this article)

Tyson, Pretty cool! Scientific American huh? Pretty impressive! 5 supernova stars! MW


 * Mole Day-** Back in the kilogram article I mentioned the term, "Avogadro's constant", though at that time I had really no idea of what the term meant......... until today. Amadeo Avogadro was a physics professor who hypothesized that at a fixed temperature and pressure, equal volumes of gases contained the same number of molecules. Though Avogadro was not blessed with fame and recognition in his lifetime, his work was not done in vain. His discoveries pretty much created the foundation for the future scientific achievement of discovering the mole. (Of which credit is given to Robert Brown) As we learned in class, the mole ,which is approximately 6.022x10^23, is a constant which can be used to find the number of atoms/other formula units, in a substance once the substance's mass is known. The number really isn't comprehensible as there would not be a mole of anything on this earth that is visible to the human eye. Although the establishment of the mole is really only applicable to the scientific community, (specifically chemists), the mole has greatly impacted the whole world, as without the mole some of the essential 21st century man-made compounds might not have been created.

Tyson, Good thoughts and connections to prior learning. 5 stars. MW


 * Dust Explosion**- When one first hears the word sugar, the thought of "merciless fire" is not usually the first that comes to mind. Sadly that is exactly what happened in a Georgia sugar plant in which 9 people were killed and 16 were seriously injured. The tragedy occurs in such factories such as the one in Georgia when a fine layer of "dust" is formed throughout the working area. Because the smaller a spherical object is, the greater the surface area to volume ratio, these fine dust particles that are created in such factories as a result of imperfect mechanical handling are very explosive due to the fact that they need much less energy for them to combust and react with oxygen. So pretty much, once the conditions are met, the situation becomes a disaster imminently waiting to happen, as something like a simple static shock could ignite the monster. After the spark, the process then proceeds to a domino effect as subsequently larger explosions are triggered since there is dust everywhere in a factory. As a result of the multitude of tragic incidents brought by this phenomena over the years, there is now much debate over the safety conditions of factory environment.

Tyson, A very well constructed post! 5 big sugar dust stars!!! MW

// __Facts I knew:__ // **
 * Helium and Sulfur Hexafluoride+Density-
 * 1) ** Helium balloons rise, and if helium is inhaled, will make your voice sound higher in pitch. **
 * 2) As you go higher up, (farther from Earth) into the atmosphere pressure decreases.
 * 3) Density is the reason that objects rise and fall, objects with particles that are more condensed and closer together have a higher density and thus fall; and vise versa.

__Facts I learned after reading:__ Tyson, Good stuff. Looks like you picked out some good stuff from these article(s) MW
 * 1) The reason that helium balloons get smaller when left alone in ordinary conditions is that the helium molecules leak out faster then oxygen and nitrogen molecules leak in.
 * 2) There is something known as the buoyant force on Earth, which due to the principle that higher altitudes warrant lower pressures, causes a small upwards force that counteracts gravity for all objects. When the force of gravity becomes inferior to the upwards buoyant force on an object, that object rises.
 * 3) Archimedes principle states that the buoyant force acting upwards on an object is exactly equal to the weight of the fluid that is being displaced.

__Facts I Knew:__ ** __Facts I learned after reading:__ Tyson, Cool beans! You have some great stuff that you knew and learned!! 5 stars! MW
 * Motion Detectors-
 * 1) I was familiar with the first type of motion detector mentioned in which a light source is aimed at a photo sensor, and when a object disrupts the stream of light by blocking it, motion is detected. (This is how my garage works)
 * 2) I was also pretty familiar with the second method of motion detection described in the article which was the radio wave echolocation sensor that monitors reflection pattern. I recall perhaps it was around sixth grade, when we were learning about bats in science class, and the teacher described how their use of echolocation aids them in obtaining food.
 * 3) Both from in class, as well as I think some book I might have read in the past, I also knew that light could be said to posses both the properties of a wave, as well as that of a particle (photons).
 * 1) I learned that the specific mechanism by which the human eye performs its function is that visible light pushes around the electrons in a cis-retina molecule which then causes a domino effect of chemical reactions to be initiated that result in the "seeing" of "color".
 * 2) I learned that it was actually Einstein's work on the photoelectric effect that won him the Nobel Prize in physics in 1921. (the photoelectric effect is the ability of light to initiate an electric current)
 * 3) I learned that rattlesnakes have special receptors at the sides of their heads, "pits", that allow them to see into the infrared spectrum. (I was on the Envirothon team for 5 years yet I didn't know about this.)