Describe the structure of a fatty acid?

Answer 1

They consist of:

carbon atoms

oxygen atoms

hydrogen atoms

They are long chains, and have double bonds between some of their carbon atoms.

monounsaturated fats have ONE double bond.

polyunsaturated fats have MANY double bonds

Answer 2

A fatty acid is a long hydrocarbon chain with a carboxylic acid functional group at one end. It can be saturated (no double bonds) or unsaturated (with double bonds). Unsaturated fatty acids can have one or more double bonds, which introduce kinks in the chain.

Answer 3

First, let's start with the structure of a carboxylic acid. You may already know that all carboxylic acids have the following structure:

O

HO-C-R, where R=hydrogen, an alkyl group, an acyl group, or an aryl group.

A "fatty acid" is a carboxylic acid where R is a long-chain alkyl group, and an "alkyl group" simply means that the group, a particular part of a molecule, is a hydrocarbon, i.e. it only contains carbon and hydrogen; no oxygen or any other elements. There is no set rule that says how many carbons the alkyl group must have to be called a fatty acid, but most chemists would probably agree that if the R group contains more than four carbon atoms, then the compound would qualify as a fatty acid. The reason has to do with the solubility of the carboxylic acids in water. When R=hydrogen, the compound is formic acid (The compound fire ants release under one's skin when they bite, causing the bite to burn.) which is completely soluble in water. If R is a methyl group (-CH3), then the compound is acetic acid, the dilute form of which is vinegar, and it is also completely soluble in water. If R is an ethyl group (-CH2CH3), then the compound is called propionic acid, and it is miscible with water also. Butyric acid, the official name of which is "butanoic acid," has a total of four carbons and its R group is -CH2CH2CH3. It has a terrible smell and is the main contributor to BO and the odor of human vomit. However, butyric acid is also soluble in water in all proportions. Now when we get to the carboxylic acid where R is a butyl group, -CH2CH2CH2CH3, the compound is called "pentanoic acid" since the prefix "pent" means five, as in a pentagon, and the compound has a total of five carbon atoms. Pentanoic acid is better known as valeric acid. I've had the misfortune of smelling it, and it is one of the worst things I've ever smelled. More importantly, pentanoic acid is only somewhat soluble in water such that if more than about 4.7 g of it is added to 100 mL of water, a layer of the compound would float on top of the water as a separate layer. The same is true for any carboxylic acid where R has more than four carbon atoms. For this reason and because the compounds feel like a fat or oil in that they are greasy and hard to wash off, all of them are called "fatty acids."

It is also important to know that the R group of fatty acids does not have to be saturated. A "saturated" hydrocarbon has no double or triple carbon-carbon (C-C) bonds. Oils and fats produced by plants generally contain a greater percentage of fatty acids where the R groups contain at least one C-C double bond. Fatty acids with only one C-C double bond are said to be "monounsaturated." If the R group contains more than one C-C double bond, then the fatty acid is "polyunsaturated." There are a few fats and oils that contain C-C triple bonds, but they are not very common.

I would like to clarify two additional items that are sometimes confusing to those first learning about fats and oils: 1) Fats and oils, regardless of whether they come from plants or animals, contain little or no individual fatty acids. Rather they exist almost entirely as triglycerides. As the name suggests, each triglyceride contains three fatty acid residues bound to one molecule of glycerine via three ester linkages. A molecule of glycerine has three hydroxyl, or -OH, groups. Specific enzymes in plants and animals catalyze condensation reactions between a fatty acid molecule and one of the -OH groups of glycerine to form a glycerine ester of that fatty acid. In the course of each fatty acid/-OH reaction, one molecule of water is liberated. Our bodies have another set of enzymes to perform the reverse of the reaction just described. Since a molecule of water was released for every glycerine ester bond formed with a fatty acid, a molecule of water is required to perform the opposite reaction called a hydrolysis, which literally means "cleaved by water" in Latin. Complete hydrolysis of each triglyceride releases three free fatty acids and one molecule of glycerine. The same reaction may be performed in a laboratory by vigorously mixing and gently heating a mixture of triglycerides, water, and an acid or a base. 2) Triglycerides that are solid at room temperature are typically called "fats," and triglycerides that are liquid at room temperature are normally referred to as "oils." The more saturated and the more carbon atoms the three fatty acids in a triglyceride are and have, respectively, the higher the melting point. The three R groups in triglycerides that are liquid at RT, like olive oil, soybean, canola, peanut, sunflower, and many others contain more carbon-carbon double bonds. The R groups in triglycerides that come from animals, including butter, contain more saturated fatty acids.

Answer 4

An acid group at one end attached to a hydrocarbon chain.

The shortest fatty acid is acetic acid (as in vinegar), its hydrocarbon chain is only one single methyl group (CH3). It is a saturated fatty acid, by default.

Answer 5

There is no set formula for fatty acids; they differ depending on the lipid. But in general, fatty acids are composed of a carbon skeleton, 16-18 carbons long. Each carbon is covalently bonded to a hydrogen. If they are double bonded, then the molecule is "unsaturated" and if there are no double bonds, then the carbons are bonded to the maximum number of hydrogens and is "saturated". The chain ends with a carboxyl group which bonds to the hydroxyl group of the glycerol in an ester linkage through a condensation (dehydration) reaction.

Answer 6

They consist of:

carbon atoms

oxygen atoms

hydrogen atoms

They are long chains, and have double bonds between some of their carbon atoms.

monounsaturated fats have ONE double bond.

polyunsaturated fats have MANY double bonds

Answer 7

Placing a question mark at the end of a list of expressions or numbers does not make it a sensible question. There is insufficient information for us to even begin to understand this question. Try to use a whole sentence to describe what it is that you want answered. Please edit the question to include more context or relevant information.

Answer 8

Both fats and oils (occurring in plants and animals) have a basic structure consisting largely of mixtures of triacylglycerols (also known as triglycerides or neutral fats). These nonpolar, water-insoluble (highly hydrophobic) substances are fatty acids triesters of glycerol.

Answer 9

First of all a 'Fatty Acid' is the old name for 'Carboxylic Acids.

A carboxylic acid is an organic structure with the following functional group

'R- C (=O) - O - H, often shortened to RCOOH .

The 'R' can be any carbon (Organic) structure. The functional group is ALWAYS on the end of a carbon chain .

Here are some examples.

Ethanoic(Acetic) Acid ; CH3-COOH

Propenoic Acid ; CH2=CH-COOH

3-Butynoic Acid ; CH3-C///C-COOH

4-Butynoic Acid ; H-C///C-CH2-COOH

Answer 10

Describe the structure and function of fatty acid molecules