Organic Chem Lab Midterm
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Why is gravity filtration and not suction filtration used to remove suspended impurities from a hot solution?
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Gravity filtration is used to remove suspended impurities from a hot solution. This is so, because if vacuum filtration is used, the lower pressure of the suction flask would cause the filtrate to boil. If this happened, the material in solution would be deposited over the walls of the flask.
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Why is a fluted filter paper used in gravity filtration?
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To increase the speed and efficiency of filtration by increasing surface area.
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Why are stemless funnels use instead of long stem funnels to filter hot solutions through filter paper?
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Because if you use a long-stemmed funnel, the crystals block the funnel as the solution cools.
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In fractional distillation, liquid can be seen from the bottom of the distillation column, back into the distilling flask. What effect does this returning condensate on the fractional distillation?
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Each successive condensation-vaporization cycle will produce a vapor that is richer in the more volatile substance, allowing for the substance with a lower boiling point to be distilled.
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Why is better separation of two liquids achieved by slow rather than fast distillation?
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because faster distillation usually means higher temperature. Under the circumstances, the mixture often evaporates too quickly for the two liquids to separate properly. Also, distillation work on the principle of different boiling points for two liquids, if you distillate too quickly, its easy to overrun the first boiling point and get a bunch of unwanted impurities.
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Review dyes and dyeing
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Review extractions, know how to make a flow chart
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Acid Permanganate Test
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1 drop KMnO4 and 1 drop 10% H2SO4
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Dimethylaniline
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Carbon ring attached to Nitrogen. Nitrogen is attached to 2 methyl groups.
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Dimethulaniline resonance structure
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Carbon ring with double bond on left and right with Hydrogen bonded to bottom Carbon and double bonded Nitrogen on top. Nitrogen has two bonds on it
