Do you know the topic today? §What is the similarity among these drinks?

The above drinks contain …….

Introduction of §Homologous series: Alkanols § Common name: Alcohols §General Formula C n H 2n+1 OH or (R-OH) §Functional Group - the hydroxyl group -OH

IUPAC System of Naming §Choose the longest continuous carbon chain that contains the -OH group § The last letter - e of the corresponding alkane is changed to - ol

IUPAC System of Naming Alkanol: §Examples CH 3 OHmethanol CH 3 CH 2 OHethanol CH 3 CH 2 CH 2 OHpropan-1-ol CH 3 CHCH 3 propan-2-ol OH CH 3 CH 2 CH 2 CH 2 OH butan-1-ol

IUPAC System of Naming Alkanol: §e.g. Name the following compound Answer : 2-methylpropan-2-ol CH 3 CH 3 - C - CH 3 OH

Manufacture of Ethanol There are 2 preparation methods:- 1. Ethanol prepared from hydration of ethene 2. Ethanol prepared from Fermentation of some sugar or starch containing food

Ethanol from ethene §Industrial ethanol is formed from ethene, a petroleum product. §The flow diagram for ethanol manufacture by direct hydration of ethene Ethene  steam  FurnaceReactor Condensor ethanol + water is formed

§The chemical equation: CH 2 =CH 2 + H 2 O  C 2 H 5 OH

Ethanol from fermentation Fermentation is the slow breakdown of large molecules to smaller molecules by micro-organism.

The sources are used §Ethanol has been made by fermentation for several thousand years. §The raw material is some form of starch or sugar such as : wheatrice potatoesgrapes apple &

barley

-Different Source can make different Alcoholic drinks.

Micro-organisms used –– Yeast §Zymase is an enzyme present in yeast. §Act as catalyst. §Conditions: room temperature and pressure. §Converts sugar to ethanol and CO 2. §For example: Glucose C 6 H 12 O 6, C 6 H 12 O 6 (aq)  2CH 3 CH 2 OH ( )  2CO 2 (g) glucose ethanol CO 2

Fermentation of glucose in laboratory Solution of glucose with yeast Lime water ? CO 2

How to obtain a max. concentration of ethanol from fermentation §The yeast is killed when the proportion of ethanol reaches about 15%. §To obtain a further concentration of the solution, fractional distillation is used. §Max. concentration of the distillate is about 96%. §Pure ethanol (absolute ethanol) is obtained by using CaO (drying agent) to removed the traces of the water.

1.Physical Uses 2. Chemical Uses Solvents Beverage Disinfectant Vinegar Synthesis Ester Synthesis 3. Fuel Gasohol (a mixtrue of ethanol and petrol 4. Preparation of ester and ethanoic acid

Uses A. Used as Solvent A. Polar Group -OH B. Non-Polar Group CH 3 CH 2 -  Water Soluble  Oil Soluble Hence, Ethanol is Soluble in Both water and Oil Because Ethanol (CH 3 CH 2 OH)contains :

Compare the solubility in water of alkane and alkene with that of alknaol? Alkane and alkene have very low solubilities in water since there is no polar group in their structures but only hydrocarbon chains, therefore they are only soluble in non-polar solvent.

Uses B. Used as Bervage Hence, ethanol is used as Bervage Because Ethanol (CH 3 CH 2 OH)contains : Ethanol is used as bervage because of its  GOOD TASTE  Thinning of blood and less prone to heart disease  PROVIDE A RELEX SENSE

Chemical Uses A. Used as Fuel As much heat is given out from the above reaction, ethanol can be burnt as fuel Because burning of Ethanol (CH 3 CH 2 OH)is highly exothermic CH 3 CH 2 OH + 4 O 2 3CO H 2 O

Ethanol can be used as Fuel for motor cars. A dvantage: - cleaner then burning petroleum. Disadvantage:- it is less powerful than petrol Gasohol is a mixture of ethanol and petrol

B. Used in preparation of Ester The Ester (with sweet smell) formed can be used as a food flavoring, perfumes and cosmetics. Because Ethanol (CH 3 CH 2 OH) react with Ethanoic Acid to form Ester Chemical Uses CH 3 CH 2 OH + CH 3 C OH O CH 3 C OCH 2 CH 3 O

C. Used in synthesis of Vinegar The Ethanoic acid formed is used as a main component in Vinegar. Because Ethanol (CH 3 CH 2 OH) react with Oxidizing agent to form Ethanoic acid CH 3 CH 2 OH CH 3 C OH O Chemical Uses [O]

Effects of Alcoholic Drinks §All are poisonous §Methanol (CH 3 OH) is toxic §All alcoholic drinks contain ethanol §Small amounts can help the thinning of blood and less prone to heart disease, but Large amounts is dangerous. §Taken in large amount has an immediate bad effect of mental and physical performance.

Effects of Alcoholic Drinks §It affects the normal functioning of the nervous system §Excessive drinking of alcohol over a long period of time, leads to damage of liver and loss of memory §People may become addicted to it §Many health, family and social problems are due to these alcoholics

Advice: DO NOT Addict to Alcoholic drinks

Revision The general formula of alkanol is A.C n H 2n OH B.C n H 2n+2 OH C.C n H 2n+1 OH D.C n H 2n-1 OH D C B A Press the pink button

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Introducing Alkanols §The general formula: C n H 2n+1 OH or ROH §The molecule consist of a functional group - the __________ group (-OH) joined to an _________ group (R-). Revision hydroxyl alkyl

2. Ethanol can be formed by two methods. They are Equation: CH 2 =CH 2 + H 2 O  C 2 H 5 OH ? Hydration of ethene ? Fermentation of sugar or starch containing food Equation: C 6 H 12 O 6 (aq)  CH 3 CH 2 OH (l)  CO 2 (g) OR

The FIVE uses of Ethanol Use as disinfectant Use as Solvent Use as Bervage Use as Fuel Use in preparation of Ester Use in synthesis of Vinegar

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