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Organic Chemistry Introduction - kl669ww - ۱۴۰۰/۱۰/۲۹ ۰۸:۱۷ صبح
دیدن لینک ها برای شما امکان پذیر نیست. لطفا ثبت نام کنید یا وارد حساب خود شوید تا بتوانید لینک ها را ببینید.
is more than simply the study of carbon or the study of chemicals in living organisms. Organic chemistry is everywhere.
What Organic Chemistry IsOrganic chemistry is the study of carbon and the study of the chemistry of life. Since not all carbon reactions are organic, another way to look at organic chemistry would be to consider it the study of molecules containing the carbon-hydrogen (C-H) bond and their reactions.
Why Organic Chemistry Is ImportantOrganic chemistry is important because it is the study of life and all of the chemical reactions related to life. Several careers apply an understanding of organic chemistry, such as doctors, veterinarians, dentists, pharmacologists, chemical engineers, and chemists. Organic chemistry plays a part in the development of common household chemicals, foods, plastics, drugs, and fuels most of the chemicals part of daily life.
What Does an Organic Chemist DoesAn organic chemist is a chemist with a college degree in chemistry. Typically this would be a doctorate or master's degree in organic chemistry, though a bachelor's degree in chemistry may be sufficient for some entry-level positions. Organic chemists usually conduct research and development in a laboratory setting. Projects that would use organic chemists would include the development of a better painkilling drug, formulating a shampoo that would result in silkier hair, making a stain resistant carpet, or finding a non-toxic insect repellent.What are Life Sciences?The simplest way to define life sciences is the study of living organisms and life processes.At NCBiotech, we see it as science involving cells and their components, دیدن لینک ها برای شما امکان پذیر نیست. لطفا ثبت نام کنید یا وارد حساب خود شوید تا بتوانید لینک ها را ببینید.
and processes. Biology, medicine and agriculture are the most obvious examples of the discipline. However, as science becomes ever more complex, it is more difficult to find clear definitions and boundaries.What is Biotechnology?Biotechnology is the most prominent component of the دیدن لینک ها برای شما امکان پذیر نیست. لطفا ثبت نام کنید یا وارد حساب خود شوید تا بتوانید لینک ها را ببینید.
s. Simply put, biotechnology is a toolbox that leverages our understanding of the natural sciences to create solutions for many of our world problems. We use biotechnology to grow food to feed our families and to make medicines and vaccines to fight diseases. We are even turning to biotechnology to find alternatives to fossil-based fuels for a cleaner, healthier planet.Brewing BiotechOften we think of biotechnology as a new area for exploration. But its rich history dates back to 8000 B.C. when the domestication of crops and livestock made it possible for civilizations to prosper. Some timelines date biotech to the Sumerians brewing beer.The 17th-century discovery of cells and later discoveries of proteins and genes had a tremendous impact on the evolution of biotechnology and life as we know it.How Biotechnology WorksBiotechnology is grounded in the pure biological sciences of genetics, microbiology, animal cell cultures, molecular biology, embryology and cell biology. The discoveries of biotechnology are intimately entwined in the life sciences industry sectors for development in agricultural biotechnology, biomanufacturing, human health, precision medicine and medical devices and diagnostics. For example, biomedical researchers use their understanding of genes, cells and proteins to pinpoint the differences between diseased and healthy cells. Once they discover how diseased cells are altered, researchers can more easily develop new medical diagnostics, devices and therapies to treat diseases and chronic conditions.What is a catalyst?دیدن لینک ها برای شما امکان پذیر نیست. لطفا ثبت نام کنید یا وارد حساب خود شوید تا بتوانید لینک ها را ببینید.
are the unsung heroes of the chemical reactions that make human society tick. A catalyst is some material that speeds up chemical reactions. With a helping hand from a catalyst, molecules that might take years to interact can now do so in seconds. Factories rely on catalysts to make everything from plastic to drugs. Catalysts help process petroleum and coal into liquid fuels. They’re key players in clean-energy technologies. Natural catalysts in the body — known as enzymes — even play important roles in digestion and more.During any chemical reaction, molecules break chemical bonds between their atoms. The atoms also make new bonds with different atoms. This is like swapping partners at a square dance. Sometimes, those partnerships are easy to break. A molecule may have certain properties that let it lure away atoms from another molecule. But in stable partnerships, the molecules are content as they are. Left together for a very long period of time, a few might eventually switch partners. But there’s no mass frenzy of bond breaking and rebuilding.Catalysts make such a breaking and rebuilding happen more efficiently. They do this by lowering the activation energy for the chemical reaction. Activation energy is the amount of energy needed to allow the chemical reaction to occur. The catalyst just changes the path to the new chemical partnership. It builds the equivalent of a paved highway to bypass a bumpy dirt road. A catalyst doesn’t get used up in the reaction, though. Like a wingman, it encourages other molecules to react. Once they do, it bows out.Enzymes are biology’s natural catalysts. They play a role in everything from copying genetic material to breaking down food and nutrients. Manufacturers often create catalysts to speed processes in industry.Transition metals are any of various metallic elements such as chromium, iron and nickel that have valence electrons in two shells instead of only one. A valence electron refers to a single electron that is responsible for the chemical properties of the atom. Transition metals are good دیدن لینک ها برای شما امکان پذیر نیست. لطفا ثبت نام کنید یا وارد حساب خود شوید تا بتوانید لینک ها را ببینید.
because they easily lend and take electrons from other molecules. A catalyst is a chemical substance that, when added to a chemical reaction, does not affect the thermodynamics of a reaction but increases the rate of reaction.Effect of Catalysts[size=medium]
Catalysts work by catalytic pathways into the reaction. They increase the frequency of collisions between reactants but do not change their physical or chemical properties. Catalysts affect the rate of reaction without affecting the thermodynamics. Catalysts thus provide an alternative, lower-energy pathway for the reaction to take place. A catalyst affects the transition state of a reaction by providing the transition state a lower-energy-activation path.
Transition Metals[size=medium]
Transition metals are often confused with "d-block" metals in the periodic table. Although transition metals belong to the d-block of the periodic table of the elements, not all d-block metals can be called transition metals. For instance, scandium and zinc are not transition metals, although they are d-block elements. For a d-block element to be a transition metal, it must possess an incompletely filled d-orbital.
[size=medium]Solvents often get sidelined in chemistry. While the choice of solvent does matter hugely, there seem to be no clear-cut rules on why a reaction sometimes works better in one solvent than another. I can say from experience that searching for the perfect solvent through seemingly endless screening is not something many chemists enjoy. So I was surprised to discover that a class of solvents was once voted the ‘British innovation most likely to shape the 21st century’ in a nationwide poll run by science museums and learned societies, sharing the honour with things like the Higgs boson, 3D-printed organs and the Raspberry Pi computer.[size=medium]But the compounds that won the vote aren’t just any old solvent; they’re probably some of the most fascinating liquids on the planet, not made from individual atoms, but entirely from anions and cations. That means these liquids are essentially salts, and that – at least according to high school science textbooks – means they should form nice solid lattice structures, not be liquid at room temperature. Enter دیدن لینک ها برای شما امکان پذیر نیست. لطفا ثبت نام کنید یا وارد حساب خود شوید تا بتوانید لینک ها را ببینید.
. Here’s Jason Bara, a professor of chemical engineering at the University of Alabama.[size=medium]Jason Bara[size=medium]Sodium chloride can be an ionic liquid if you get it hot enough. But I guess the modern definition is organic salts that melt below 100 degrees Celsius. And then after that, it kind of became salts that melt below room temperature, so then those are the ones that got really a lot of interest over the last 20 years or something like that is the ones that are liquids at room temperature.[size=medium]So in a sense, ionic liquids are nothing more than molten salts. But when you think of ‘salts’, you might think of ‘sodium chloride’ and it’s ridiculous 800°C melting point. A new description was needed – and the phrase ‘ionic liquid’ was born. Other names include liquid salts, ionic melts, fused salts, or, if you want to be particularly elegant, ionic glasses.[size=medium]The most common ionic liquids are made up of an organic cation, usually an alkylated amine, and an inorganic anion, often a borate, sulfate or phosphate. The reason they’re liquid? Simple sterics.