알켄과 알코올의 간단 구별(구분) 실험방법

알켄과 알코올의 간단 구별(구분) 실험방법

 

 

CH3CH2CH=CHCH3와 CH3CH2CH(OH)CH2CH3를 분간하기 위한 간단한 실험을 제안하시오.

 

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CH3CH2CH=CHCH3 : 알켄, pent-2-ene, 2-pentene

CH3CH2CH(OH)CH2CH3 : 2차 알코올, 3-pentanol

 

 

[출처] How to Tell the Difference Between Alcohol & Alkene in Labs

http://classroom.synonym.com/tell-difference-between-alcohol-alkene-labs-15368.html

 

 

[Bromine Reaction]

Another common test is the addition of liquid bromine, which is brownish-purple in color. Bromine quickly reacts with alkenes to add a bromine atom to each one of the carbons on either side of the double bond. When you add bromine and water to a chemical and the color rapidly disappears, it may contain an alkene that is reacting with the bromine. This test is much more selective for alkenes than Baeyer's Test and therefore a better way to confirm your compound has a double bond.

 

브롬수(liquid bromine)를 가하면, 알켄은 반응(브롬의 색깔인 자줏빛 갈색이 사라짐)하고, 알코올은 반응하지 않습니다(변화 없음).

 

 

[Lucas Test]

The first of the many tests for alcohol is the Lucas test, whereby you add zinc chloride and concentrated hydrochloric acid to your compound. If it contains an alcohol attached to a carbon atom that has three other carbons bonded to it, known as a tertiary alcohol, a rapid reaction will produce a cloudy precipitate. A so-called secondary alcohol, attached to a carbon with two other carbons attached to it, reacts more slowly, producing a precipitate within five minutes or so. And alkenes, as well as primary alcohols wherein the alcohol group is attached to a carbon with only one other carbon bonded to it, do not react. This test is especially useful because it not only tells you whether you have an alcohol but gives you some idea of where the alcohol group may be located in the molecule.

 

[염화아연 + 진한 염산]을 가하면, 3차, 2차 알코올은 반응(회색 침전 발생)하고, 알켄은 반응하지 않습니다(변화 없음).