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Reaction with Sodium Small pieces of sodium (2-3 turn} are placed in: 1) water

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Reaction with Sodium Small pieces of sodium (2-3 turn} are placed in: 1) water. 2) ethanol (I00 14.). 3) 2- butanol. and 4} 2-methyl-2-propanol. Record any salient observations, B. Solubility in Water intensity To I n'tL of water in a [3 it IOU-mm test tube. add the alcohol being tested. drop by drop. and shake the tube to mix the two materials. Perform this experiment with ethanol. 2-pr0panol. l -butanol. cyclohexanol and your unknown. Record your results: 1:. Lucas'test Place 2 ml. of the Lucas reagent in a [3 l. lilo-mm test tube, add 4 drops of the alcohol to be tested, shake the tube to mix the materials, and note the time required for the mixture to become cloudy or to separate into me layers. Try the test on i -butano]. 2-butanol, 2-methyl-2- propanol. and your unknown. (Note: The alcohol must dissolve initially.) D. Oxidation Using Chronic Acid (Jones Reagent} Place ] ml. of acetone in a [3 x IDB-rnm test tube {acetone that is free oftraces of alcohol must be used); add 1 drop ofthe alcohol to be tested and then 2 drops ofthe chromic acid reagent. Note whether the mixture stays clear and orange {the color of the unreacted C103) or turns turbid blue-green [formation oI'Cr (III}]. Make the decision about the test within 5 seconds since 3" alcohols undergo slow dehydration to an alkene with its subsequent oxidation by the Jones reagent a?er a few minutes. Perform this test on I —butanol, 2-butanol, 2-methyl-2- propanol. and your unknown. E, Ester Formation Mix 5 drops oi the alcohol to be tested and 5 drops of glacial acetic acid in a 13:100-mm test tube. Add 1 drop of concentrated Sulfuric acid, warm the mixture gently [3 to 4 in a hot water bath], and then add 2 mL of cold water. Note the odor {if you have trouble detecting the odor or if the odor is masked by the acetic acid, pour the mixture into a small beaker and make it slightly basic with 10% NaDH]. Perform this experiment on 1- butanol, 3-methyl-1-butanol, and your unknown. Based on the results of these tests indicate whether your unknown is a 1', 2', or 3" alcohol and whether it has a low or high molar mass.

Properties of Alcohols Introduction: Among the most important compounds in organic chemistry are the alcohols. Alcohols contain a hydroxy group (-OH) attached to an alkyl group. Alcohols are important intermediates in organic synthesis since they can be readily converted into alkyl halides, alkenes, aldehydes, ketones, and carboxylic acids. However, alcohols are very important in their own right. Ethyl alcohol (ethanol)). of course, has been consumed by human beings for over ten thousand years in alcoholic beverages such as beer, wine and distilled spirits such as whiskey, bourbon, rum, vodka, brandy, etc. It has also been used as a fuel and has been gaining usage as a component of gasoline. It's great advantage is that it is a renewable resource unlike conventional gasoline. Indeed the production of ethyl alcohol dwarfs the production of any other chemical produced by humans. Another important alcohol is ethylene glycol which because of its low melting point when mixed with water and its high boiling point is the primary component of an automobile's antifreeze. Another class of alcohols are carbohydrates which are polyalcohols (i. e., have mutiple OH groups). One important carbohydrate is glycerine (glycerol) which is used in cosmetics, soaps, lubricants, inks, and of course in the manufacture of nitroglycerine. The various sugars, such as glucose, are another important class of carbohydrates. CH, OH CH2 ONO2 CH, OH CHOH CHONO2 OH O OH HOCH, CH, OH CH, OH CH, ONOz HO OH Ethylene glycol Glycerine Nitroglycerine Glucose Several tests will be performed on a series of known alcohols and an unknown alcohol. The known alcohols to be used in these experiments are ethanol (ethyl alcohol), 1-butanol (n- butylalcohol), 2-butanol (sec-butyl alcohol), 2-methyl-2propanol (t-butyl alcohol), and cyclohexanol. Using these tests an unknown alcohol will be identified as either 1 . 20, or 3 and as low molar mass (molecular weight) or high molar mass. The tests to be performed are: A) reaction with sodium (as a demonstration by your instructor). B) solubility/density, C) the Lucas Test, D) oxidation using chromic acid, and E) ester formation. Only one equation need be shown as an example for the tests in A, C, D, and E. The reactivity with sodium is sterically controlled. Because the -OH group of alcohols hydrogen bond well with water, lower molar mass alcohols are soluble in water, however as the number of carbons increases the molecule becomes more and more nonpolar in nature and hence less soluble in water. The Lucas test involves formation of alkyl chlorides via carbocations in the rate determining step of an SN1reaction. Oxidation of alcohols occur readily only for 10 and 20 alcohols where the 10 alcohols are oxidized to carboxylic acids and the 2" alcohols to ketones. Volatile esters (MM< 150) often have very pleasant sweet, fruity odors. Indeed the ester formed here between acetic acid and 3-methyl-1-butanol (iso-amyl alcohol) has the common name banana oil. The rate of the reaction is an important observation in A, C, and D. Materials: Ethanol, absolute (ethyl alcohol), I ml 1-butanol (n-butyl alcohol), 1 ml 2-butanol (sec-butyl alcohol), 1 ml 2-methyl-2-propanol (t-butyl alcohol), I mL Cyclohexanol, I mL 2-Methyl-1-butanol (iso-amyl alcohol), I mL Acetic acid, glacial, I mL Jones Reagent Lucas Reagent Sulfuric acid, H2SO4, conc. 1-2 drops Sodium hydroxide, 10% solution Sodium (stored in mineral oil), 1 g. Precautions: The experiment involving the reaction with sodium is done only as a demonstration by your instructor!