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Chemical reactions often need a solvent in order for them to take place.
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Can you remember what a solvent does?
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Pause the video and continue when ready.
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The answer is that a solvent will dissolve a solute.
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This means that two or more soluble compounds made them react with one another to form the new product.
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The issues are that a lot of chemical processes involve organic solvents.
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That is those containing carbon and hydrogen, and sometimes halogen groups.
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Organic solvents are usually obtained from the fractional distillation of crude oil.
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This is an environmentally unfriendly process which uses a lot of energy and produces greenhouse gases.
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Also the solvents themselves are usually environmentally unfriendly and need to be disposed of carefully.
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Chemists around the world are looking towards green chemistry and the development of safer solvents.
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It may sound surprising but these safer solvents include special forms of water and carbon dioxide which exist in a supercritical state.
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Essentially this means at a certain temperature these solvents will exist as a solid, liquid, and gas simultaneously.
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You may be wondering why this is important.
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The reason is that non-polar compounds traditionally needing organic solvents can be dissolved in a safer solvent.
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More importantly, carbon dioxide and water are not flammable like most organic solvents and are very easy to obtain from other chemical processes.
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Imagine instead of releasing carbon dioxide into the air and it contributing to global warming we can collect it and use it as a solvent instead.
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This has been especially useful to the dry cleaning and textiles industries.