Alcohol and carboxylic acid

Chapter 4: Carbon and Its Compounds

1. Alcohols and Carboxylic Acids Chapter 4: Carbon and its Compounds 1 Archana Singh

2. An atom or group of atoms that is responsible for the specific properties of an organic compound Compounds that contain the same functional group can be classed together Makes properties that are very different from those of the corresponding hydrocarbon. Functional Groups 2 Archana Singh

3. Alcohol 3 Archana Singh

4. C 2 H 5 OH 4 Archana Singh

5. 5 In chemistry, an alcohol is any organic compound in which a hydroxyl group ( -OH ) is bound to a carbon atom of an alkyl group . The general formula for a simple acyclic alcohol is CnH2n+1OH. Archana Singh

6. 6 In common terms, the word alcohol refers to ethanol , the type of alcohol found in alcoholic beverages . Ethanol is the most widely used depressant in the world, and has been for thousands of years. This sense underlies the term alcoholism ( addiction to alcohol). Archana Singh

7. Belong to a homologous series of organic compounds similar to alkanes and alkenes. The hydrocarbon chains contain the functional group -OH (hydroxyl group) What are Alcohols ? Structural Formula Chemical Formula C 2 H 5 OH (molecular formula) or CH 3 CH 2 OH (condensed structural formula) = OH 7 Archana Singh

8. Alcohols are soluble in water but their solubility decreases as their molecular size increases. Unlike the alkanes and alkenes, the first four alcohols are liquid at room temperature and pressure. Although alcohols contain the –OH group, they are not alkalis. In fact, they are all neutral . Physical Properties of Alcohols 8 Archana Singh

9. Naming the Alcohol Methan ol Total of one carbon atom (meth-) CH 3 OH Ethan ol Total of two carbons atoms (eth-) CH 3 CH 2 OH Propan ol Total of three carbon atoms ( propan - ) C 2 H 5 CH 2 OH *Take note of the functional group’s location, highlighted by the dotted box OH OH OH 9 Archana Singh

10. No. of carbon atoms Name of Alcohol Molecular Formula Structural Formula Condensed Structural Formula 1 Methanol CH 3 OH CH 3 OH 2 Ethanol C 2 H 5 OH CH 3 CH 2 OH 3 Propanol C 3 H 7 OH CH 3 (CH 2 )CH 2 OH 4 Butanol C 4 H 9 OH CH 3 (CH 2 ) 2 CH 2 OH 5 Pentanol C 5 H 11 OH CH 3 (CH 2 ) 3 CH 2 OH Naming the Alcohol OH OH OH OH OH 10 Archana Singh

11. The names of alcohol end with ol . Alcohol are a homologous series with the general formula C n H n+1 OH, where n is the number of carbon atoms in a molecule. The simplest alcohol is methanol , with one carbon atom. Naming the Alcohol 11 Archana Singh

12. Alcohols are soluble in water but their solubility decreases as their molecular size increases. Unlike the alkanes and alkenes, the first four alcohols are liquid at room temperature and pressure. Although alcohols contain the –OH group, they are not alkalis. In fact, they are all neutral . Physical Properties of Alcohols 12 Archana Singh

13. Alcohols can take part in these reactions: Combustion and Oxidation Reaction with Sodium Metal Reaction to form unsaturated hydrocarbon Reaction with Carboxylic acid to form Esters Chemical Properties of Alcohols 13 Archana Singh

14. Combustion An alcohol burns in air to produce carbon dioxide and water vapour . ethanol + oxygen → carbon dioxide + water vapour C 2 H 5 OH + 3O 2 → 2CO 2 + 3H 2 O C 2 H 5 OH + 3O 2 → 2CO 2 + 3H 2 O 14 Archana Singh

15. Flame produced is clean Combustion of alcohols are useful because: 1. Methanol is less likely than conventional fuel to explode in an accident. It is a clean fuel. 2. When alcohol beverage is burnt with food, it gives a distinct flavour . Combustion 15 Archana Singh

16. Chemical equation: Oxidation + 2 [O] + H 2 O Ethanol Ethanoic acid 16 Archana Singh

17. The colour of potassium dichromate(VI) changes from orange to green . Oxidation of alcohol is used in:  Breathalyzer to test the amount of alcohol consumed by drivers. Oxidation 17 Archana Singh

18. The reaction between sodium and ethanol If a small piece of sodium is dropped into some ethanol, it reacts steadily to give off bubbles of hydrogen gas and leaves a colourless solution of sodium ethoxide , CH 3 CH 2 ONa. Sodium ethoxide is known as an  alkoxide . CH 3 CH 2 OH + Na CH 3 CH 2 ONa + H 2 18 Archana Singh

19. Uses of Ethanol? solvents for paints, varnishes, perfumes fuel for vehicles alcoholic drinks making ethanoic acid for preserving food and making esters ethanol oxidation 19 Archana Singh

20. How it all ties up 20 Archana Singh

21. organic compounds that contain the carboxyl functional group General formula: Like inorganic acids Carboxylic acids react to lose a hydrogen ion and become a negatively charged ion in water Carboxylic Acids 21 Archana Singh

22. Name Parent Compound Longest chain contains carboxyl group Drop –e, add – oic acid Carboxylic Acid Nomenclature C C C O propanoic acid OH C O OH C C C C O OH C O HO ethanedioic acid 22 Archana Singh