Term
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Definition
When a carboxylic acid reacts with an alcohol to form an ester and a water. The -H from the carboxylic acid is donated and an alkyl group replaces it. |
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Term
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Definition
An ester is produced when a carboxylic acid and an alcohol react in the presence of an acid catalyst (H2SO4)
The -OH is removed from the carboxylic acid and the -H is removed from the alcohol to form the ester and water.
O O
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CH3-C-OH + H-O-CH3 (acid) Heat->CH3-C-O-CH3 + H2O
Ethanoic Acid + Methanol -> Methyl acetate + H2O |
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Term
What is the IUPAC naming for Esters? |
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Definition
The first word is te alkyl part of the alcohol. The second word is the carboxylate name of the carboxylic acid (-ic replaced with -ate)
Methanol + Ethanoic Acid -> Methyl Ethanoate
O
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CH3-O-C-CH3 |
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Term
What are common names for esters? |
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Definition
Use the alkyl name of the alcohol and the common name of the acids.
Methyl alcohol + Acetic Acid = Methyl Acetate
O
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CH3-O-C-CH3 |
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Term
What are the boiling points of Esters? |
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Definition
Higher than alkanes, lower than alcohols and carboxylic acids. No hydrogen bonding is present.
Alkane -> Ether -> Ester -> Alcohol -> Carboxylic Acid |
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Term
Are esters soluble in water? |
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Definition
Smaller esters are due to the partial negativty of oxygen. Carbonyl can form hydrogen bonds with water. |
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Term
What is acid hydrolysis of esters? |
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Definition
Esters are split when heated in a strong acid in the presence of water.
O O
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Methl ethanoiate + water -> Ethanoic Acid + Methanol |
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Term
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Definition
The base hydrolysis of esters. |
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Term
How does Saponification work? |
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Definition
The reaction of a long chain fatty acid with NaOH to make soap. The carboxylic acid produced in acid hydrolysis is converted to its carboxylate ion by a strong base.
O O
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CH3-C-O-CH3 + NaOH [Heat]-> CH3-C-O-Na+ + CH3-OH
Methyl Ethanoate + Sodium hydroxide -> Sodium Ethanoiate + Methanol |
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Term
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Definition
A salt made of long chain fatty acids. The soap molecule ends have different polarities. |
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Term
What is the polarity and solubility of the carbon chain of a soap molecule? |
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Definition
Non-polar and hydrophobic. Soluble in oil and grease. |
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Term
What is the polarity and solubility of the carboxylate salt end of a soap molecule? |
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Definition
Ionic, hydrophilic and soluble in water. |
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Term
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Definition
The nonpolar ends dissolve in nonpolar fats and ols on dirt. The carboxylate salt ends dissolve in water. |
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Term
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Definition
Clusters of coated oil and grease. The ionic ends of the soap molecules provide polarity and makes them water soluble. The coated glbules are pulled into water and are rinsed away. |
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Term
What is a problem using soap? |
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Definition
The carboxylate end reacts with calcium and magnesium to form insoluble substances. |
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