Intro to Chemistry

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Intro to Chemistry발음듣기

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(light music) Hi. My name is Anne McNeil, and I'm an assistant professor here at the University of Michigan, where I study the chemistry of organic materials.발음듣기

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When I was growing up I was interested in what everything was made of and how it worked.발음듣기

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Before the internet I had to find answers to these questions in books.발음듣기

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I even got my first job at the library, so I could have access to more books.발음듣기

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I didn't really have a favorite subject at the time, because I liked all aspects of science, and it wasn't until I got to college when my professor was explaining how a rubber band get's its stretchy characteristics based on how the atoms are connected within that structure of rubber.발음듣기

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I realized that just about everything can be explained if you understand that atoms that make up that material as well as how they are connected to each other.발음듣기

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It was then that I decided that I wanted to be a chemist.발음듣기

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So chemistry is broadly defined as the study of matter.발음듣기

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The goal is to understand the structure of matter and it's composition.발음듣기

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So, understanding what elements make up that matter and how their connected to each other.발음듣기

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Then chemist can use that information about structure and composition to predict and understand its properties.발음듣기

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So, I'm showing you here a three dimensional model of caffeine.발음듣기

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We can use our understanding of the structure of caffeine to understand how it interacts with body.발음듣기

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Another example you might be familiar with is ozone.발음듣기

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As early as 1865 chemists had discovered that ozone consisted of three oxygen atoms.발음듣기

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It wasn't until much later that they discovered that the structure was actually this bent structure.발음듣기

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Based on our understanding of this bent structure we can now understand some of the properties of ozone.발음듣기

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Its ability to absorb the skin damaging UV radiation from the sun, but also some of its negative properties like it's reactivity with nitrogen oxide to generate smog.발음듣기

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So, just as the chemistry of the universe has evolved from simple hydrogen and helium to now the complex molecules of DNA that are within your body, so has our study of chemistry.발음듣기

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So in the old days people were very limited on the techniques to determine both structure and composition.발음듣기

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Instead of having some of the advanced techniques, they often resorted to tasting compounds and classifying them as bitter or sweet.발음듣기

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Now, fortunately, today we don't taste compounds anymore.발음듣기

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We have a number of techniques we can use to determine both structure and composition.발음듣기

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So, for example, if we have a crystal of caffeine, we can look at how x-rays are scattered as they pass through that crystal, and use that information to identify both the atoms, as well their [connectivity].발음듣기

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We can also inject a molecule of caffeine into a mass spectrometer and get the mass of the molecule.발음듣기

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We can use various forms of spectroscopy , which involves the absorption and emission of light to identify functional group.발음듣기

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Like a carbon oxygen double bond.발음듣기

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Using all these techniques, we are no longer limited in determining both structure and composition.발음듣기

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As a result, you'd be amazed to see many of the innovations that are coming out of labs today.발음듣기

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So, for example, we can completely replace glass bottles with plastic bottles that are easier to recycle and can even biodegrade.발음듣기

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So chemistry is often referred to as a central science, because it plays a role in some many of the other sciences.발음듣기

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So, for example, an astrochemist is involved in the search for life on Mars by looking for the distinct spectroscopic features of water on that surface.발음듣기

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Geochemist are involved in telling the history of the Earth by looking at the changes in the atomic composition of rocks over time.발음듣기

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Biochemist are involved with developing various drug molecules to help treat and cure diseases.발음듣기

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So, as chemistry is so central to all these other sciences, chemist will play a role in the future innovations in all of these fields.발음듣기

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So, for example, chemical biologist are now trying to design drugs that are specific for you based on your DNA.발음듣기

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[Analytical] chemist are trying to develop microchips that they can install and [non-invasively] monitor your health and report back to your doctor without stepping foot in a office.발음듣기

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Material chemist are developing materials that will capture sunlight efficiently and convert that directly into electricity, so that we can reduce our reliance on fossil fuels.발음듣기

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Synthetic chemist are developing catalyst that they can use to convert a greenhouse gas like co2 into a useful fuel that we can burn.발음듣기

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If you today ask a chemist what they do you often hear them say I'm a something chemist.발음듣기

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I'm a material chemist or a physical chemist or an [analytical] chemist.발음듣기

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Chemist are everywhere and their contributing to all these fields of science. (music)발음듣기

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