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Carboxylic Acids and Esters. By: Navneet , Farah, Christina and Cindy. What is it?. Carboxylic Acids: Weak acids Found in citrus fruit -COOH Esters: Found in plants Odours . Etserification.
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Carboxylic Acidsand Esters By: Navneet, Farah, Christina and Cindy
What is it? Carboxylic Acids: • Weak acids • Found in citrus fruit • -COOH Esters: • Found in plants • Odours
Etserification • A carboxylic acid reacts with an alcohol, in the presence of a catalyst, forming an ester and water. This condensation reaction is known as esterification. CH3COOH + CH3CH2OH concentrated H2SO4 CH3COOCH2CH3 + H2Oethanoic acid + ethanol catalyst (H2SO4) ethyl ethanoate + water • sulfuric acid is our catalyst. • The –OH from the alcohol bonds with the H from the ethanoic acid
Oxidation of Aldehyde Aldehyde + Oxygen Carboxylic Acid
AmideSynthesis Carboxylic Acid + Amine Amide + Water
Hydrolysis • When an ester is treated with an acid or base and water, reverse esterification occurs. CH3COOCH2CH3 + H2O dilute H2SO4 CH3COOH + CH3CH2OH • catalyst = dilute sulfuric acid
Saponification • Saponification occurs when an ester reacts with a strong base. This reaction is not reversible due to the carboxylate salt that is formed at the end of the reaction. • The sodium salt of the carboxylic acid that result are what we call soap. This process is called saponification.
Industrial Uses • synthetic odours and flavours • Ex. Benzyl acetate, from acetic acid, has a jasmine odour • ester ethyl acetate= nail polish remover • fatty acids are used in the manufacture of soaps, detergents and shampoos
Environmental Impact Pesticides/Herbicides Octyl Phenoxy Polyethoxy Enthanol Phosphate Ester • Pesticide, highly toxic Acetic acid • 10% - 20% [c]= 80% - 100% effectiveness • organic compound, not harmful to environment (long term) PFOA /PFOS PFOA = Perflouro Octanoic Acid PFOS = Perfluoro Octane Sulfuric Acid • man-made product • highly stable structure
Summary Carboxylicacid Esterification • Carboxylic Acid + Alcohol Ester + Water Oxidation of Aldehyde • Aldehyde + Oxygen Carboxylic Acid AmideSynthesis • Carboxylic Acid + Amine Amide + Water Esters Condensation reaction • Alcohol + Carboxylic Acid Ester Hydrolysisreaction (saponification) • Ester + Base Carboxylic Salt + Alcohol
Quiz! • What does PFOA stand for? • Most important industrial applications of compounds with carboxyl groups is the use of . • What is the definition of an ester? • What is the name of the reaction that splits a product into an acid and a alcohol? • Why does the melting point rise when there are more carboxylic acids present?
Bibliography "Environment Canada - Acts & Regulations - Draft Screening Assessment Perfluorooctanoic Acid, its Salts, and its Precursors."Environnement Canada - Environment Canada. N.p., n.d. Web. 24 Mar. 2012. <http://www.ec.gc.ca/lcpe-cepa/default.asp?lang=En&n=705376A7-1&offset=10&toc=show>. "Environmental Fate of Pesticides."BC Ministry of Agriculture, Food and Fisheries. N.p., n.d. Web. 24 Mar. 2012. <http://www.agf.gov.bc.ca/pesticides/c_2.htm>. Shapley, Dan. " Food Packaging Chemicals- PFOS and PFOA Chemicals from Food Packaging - The Daily Green."Going Green, Fuel Efficiency, Organic Food, and Green Living - The Daily Green. N.p., n.d. Web. 24 Mar. 2012. <http://www.thedailygreen.com/environmental-news/latest/packaging-chemicals-47050101>.