Essay on Carboxylic Acids Organic Chemistry

Submitted By Papajohn_31
Words: 1896
Pages: 8
Open Document
Chapter 20 Chapter Outline
20-1 Introduction
The functional group of carboxylic acids consists of a C═O with —OH bonded to the same carbon.
Carboxyl group is usually written —COOH.
Aliphatic acids have an alkyl group bonded to —COOH.
Aromatic acids have an aryl group.
Fatty acids are long-chain aliphatic acids.
20-2 Nomenclature of Carboxylic Acids
Many aliphatic acids have historical names.
Positions of substituents on the chain are labeled with Greek letters starting at the carbon attached to the carboxylic carbon

.
IUPAC Names
Remove the final -e from alkane name, add the ending -oic acid.
The carbon of the carboxyl group is #1.

Unsaturated Acids
Remove the final -e from alkene name, add the ending -oic acid.
Stereochemistry is specified

Aromatic Acids
Aromatic acids are named as derivatives of benzoic acid.
Ortho-, meta- and para- prefixes are used to specify the location of a second substituent.
Numbers are used to specify locations when more than 2 substituents are present.

Dicarboxylic Acids
A dicarboxylic acid (also called a diacid) is a compound with two carboxyl groups. The common names of simple dicarboxylic acids are used more frequently than their systematic names.
A common mnemonic for these names is “Oh my, such good apple pie,” standing for oxalic, malonic, succinic, glutaric, adipic, and pimelic acids.
Substituted dicarboxylic acids are given common names using Greek letters, as with the simple carboxylic acids. Greek letters are assigned beginning with the carbon atom next to the carboxyl group that is closer to the substituents
.
Benzenoid compounds with two carboxyl groups are named phthalic acids.
Phthalic acid itself is the ortho isomer. The meta isomer is called isophthalic acid, and the para isomer is called terephthalic acid.
Aliphatic dicarboxylic acids are named simply by adding the suffix -dioic acid to the name of the parent alkane. For straight-chain dicarboxylic acids, the parent alkane name is determined by using the longest continuous chain that contains both carboxyl groups. The chain is numbered beginning with the carboxyl carbon atom that is closer to the substituents, and these numbers are used to give the positions of the substituents.
20-3 Structure and Physical Properties of Carboxylic Acids
The sp2 hybrid carbonyl carbon atom is planar, with nearly trigonal bond angles.
The O—H bond also lies in this plane, eclipsed with the C═O bond.
The sp3 oxygen has a C—O—H angle of 106°.

Boiling Points
Higher boiling points than similar alcohols, due to the formation of a hydrogen-bonded dimer.

Melting Points
Aliphatic acids with more than 8 carbons are solids at room temperature.
Double bonds (especially cis) lower the melting point. The following acids all have 18 carbons:
Stearic acid (saturated): 72°C
Oleic acid (one cis double bond): 16°C
Linoleic acid (two cis double bonds): -5°C
Solubility
Water solubility decreases with the length of the carbon chain. With up to 4 carbons, acid is miscible in water. Very soluble in alcohols.
Also soluble in relatively nonpolar solvents like chloroform because the hydrogen bonds of the dimer are not disrupted by the nonpolar solvent
20-4 Acidity of Carboxylic Acids
A carboxylic acid may dissociate in water to give a proton and a carboxylate ion.
The equilibrium constant Ka for this reaction is called the acid-dissociation constant.
The acid will be mostly dissociated if the pH of the solution is higher than the pKa of the acid.

Values of are about pKa 5 1Ka = 10-5) for simple carboxylic acids. For example, acetic acid has a pKa of 4.7 (Ka = 1.8 x 10-5 ).
Energy Diagram of Carboxylic Acids and Alcohols

Stability of carboxylate ions. Carboxylic acids are more acidic than alcohols because carboxylate ions are more stable than alkoxide ions. A carboxylate ion has its negative charge delocalized over two oxygen atoms, compared with only one oxygen atom bearing the negative charge in an alkoxide ion.
Acetate Ion Structure

Each
Show More

Related Documents: Essay on Carboxylic Acids Organic Chemistry

A Level Chemistry Essay

A Level Chemistry Entry Requirements: BB in Core and Additional Science or B in Chemistry and C in Maths. In addition, a D Grade in AS Chemistry is needed to progress to the A Level. Wainwright, Miss J Rigby Exam Board: AQA Teachers: Mrs V Bates, Mr A Conheeney, Mr N Barnet, Mr P Carter, Mrs J Timetable Organisation: 5 periods of 1 hour length each week for two years, taught by 2 teachers. Students in Year 13 also have one hour of directed study time each week. Main Syllabus Area A Level Chemistry…

Words 422 - Pages 2

Essay on Chemistry Intro to Lab

important to daily life can be obtained. It is applied to all types of chemical compounds, but most syntheses are done with organic compounds such as the ones used in our labs, Carboxylic Acid and Alcohol. Esterification is the name of the reaction in which two reactants, which in our case are the Carboxylic acid and the alcohol, form an ester. Esters are used very often in organic chemistry and biological materials, and also if reacted correctly, have a pleasant odor. Due to this characteristic, Esters are…

Words 611 - Pages 3

Sch4U Final Exam Study Note Essay

Chemistry Exam Study Sheet Organic Chemistry • Study of compounds to which carbon is the principal element. • Carbon is special because it has 4 bonds. Functional Groups • Organic substances are organized into organic families. • Organic Families – group of organic compounds with common structural features. o Each family has a recognizable physical property and a specific structural arrangement. o Each combination is referred to as a functional group. o Even…

Words 2359 - Pages 10

Unit 6 Essay

Unit 6: Synthesising Organic Compounds Assignment 6.1 Isomerism in Organic Chemistry arises when molecular formulae are the same, but the arrangement of atoms is different. Describing and explaining with examples, the different types of isomerism encountered in organic chemistry by focusing on: a) Structural: including function group isomerism Stereoisomerism: i.e. geometric and optical, with explanations of how this type of isomerism arises. You must use examples to explain. Structural Isomerism…

Words 3385 - Pages 14

Primary Alcohols Essay

Alcohol In chemistry, an alcohol is any organic compound in which a hydroxyl functional group (-O[->0]H) is bound to a carbon atom, usually connected to other carbon or hydrogen atoms. Nomenclature The suffix -ol appears in the IUPAC chemical name of all substances where the hydroxyl group is the functional group with the highest priority; in substances where a higher priority group is present the prefix hydroxy- will appear in the IUPAC name. In the IUPAC system, the name of the alkane chain…

Words 920 - Pages 4

Unit 6 Essay

Unit 6: Synthesising Organic Compounds Assignment 6.1 Isomerism in Organic Chemistry arises when molecular formulae are the same, but the arrangement of atoms is different. Describing and explaining with examples, the different types of isomerism encountered in organic chemistry by focusing on: a) Structural: including function group isomerism Stereoisomerism: i.e. geometric and optical, with explanations of how this type of isomerism arises. You must use examples to explain. Structural Isomerism…

Words 3380 - Pages 14

The Scenario Essay

bottle in a recently produced batch. So therefore the purpose of the investigation in which we have been employed to carry out is to test and identify the functional group of a suspected unknown organic compound which has contaminated the tested water, through the process of organic chemistry Introduction Organic compounds, is the chemical study of carbon and its compounds. These compounds form from covalent bonds, which is the formation of molecules. The reason due to covalent bonds the only way these…

Words 356 - Pages 2

Chemistry: An Introduction To General, Organic, And Ethers

administered by a nurse anesthetist who provides care before, during, and after a medical procedure. A nurse anesthetist gives medications to keep a patient asleep and pain-free while monitoring the patient’s vital signs. Chemistry: An Introduction to General, Organic, and Biological Chemistry, Twelfth Edition © 2015 Pearson Education, Inc. 12.1 Alcohols, Phenols, Thiols, and Ethers Functional groups such as • an alcohol contain a hydroxyl group (—OH) • a phenol contain a hydroxyl group (—OH) bonded to…

Words 3381 - Pages 14

Does The Molecule Have A Plane Of Symmetry?

has been drawn with carboxylic acids represented in two different ways. The two CO2H groups are in fact the same and the molecule has a plane of symmetry (shown by the dashed lines). It isn’t chiral. Me OH OH Me OH = HO2C O OH HO2C CO2H HO2C CO2H 2 Solutions Manual to accompany Organic Chemistry 2e The second compound…

Words 1547 - Pages 7

Synthesis of Adipic Acid Essay

Experiment 8: Synthesis of Adipic Acid Performed November 8th & 10th By Jennifer Seitz Organic Chemistry 344 Section 803 Fall 2011 Objective: The purpose of this experiment was to synthesize adipic acid from cyclohexanol via an oxidation reaction that was catalyzed by sulfuric acid. Purity of the product was assessed by measuring the melting point. Physical Properties/Structures: Name | Formula | Molecular Weight (g/mol) | Boiling Point (0C) | Melting Point(0C) | Density(g/mL)…

Words 1692 - Pages 7