Unsaturated compound
Encyclopedia
In organic chemistry
, a saturated compound is a chemical compound
that has of a chain of carbon
atom
s linked together by single bonds and has hydrogen
atoms filling all of the other bonding orbitals of the carbon atoms. Alkane
s are an example of saturated compounds. An unsaturated compound is a chemical compound that contains carbon-carbon double bond
s or triple bond
s, such as those found in alkene
s or alkyne
s, respectively. Saturated and unsaturated compounds need not consist only of a carbon atom chain. They can have functional groups, as well. It is in this sense that fatty acid
s are classified as saturated
or unsaturated
. The amount of unsaturation of a fatty acid can be determined by finding its iodine number
.
In a chain of carbons, such as a fatty acid
, a double or triple bond will cause a kink in the chain. These kinks have macro-structural implications. Unsaturated fats tend to be liquid
at room temperature, rather than solid
, due to the kinks in the chain. The kinks prevent the molecule
s from packing closely together to form a solid. These fats are called oil
s and are present in fish
and plant
s.
In other unsaturated hydrocarbon
s, the double bond between two carbons prevents rotation of the atom
s about the bond, locking them into specific structural formations. When attached atoms occupy similar positions on each carbon, they are referred to as "cis", and when they are on opposite sides, they are called "trans". Most natural hydrocarbons exist in the cis state, but artificially manufactured hydrocarbons are trans. The body lacks the enzyme
s to properly break down the trans configuration. This is why trans fats are viewed as dangerous and unhealthy, as they tend to build up. Unsaturated compounds of the two formations are classified as geometric isomers of one another.
Organic chemistry
Organic chemistry is a subdiscipline within chemistry involving the scientific study of the structure, properties, composition, reactions, and preparation of carbon-based compounds, hydrocarbons, and their derivatives...
, a saturated compound is a chemical compound
Chemical compound
A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...
that has of a chain of carbon
Carbon
Carbon is the chemical element with symbol C and atomic number 6. As a member of group 14 on the periodic table, it is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds...
atom
Atom
The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...
s linked together by single bonds and has hydrogen
Hydrogen
Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...
atoms filling all of the other bonding orbitals of the carbon atoms. Alkane
Alkane
Alkanes are chemical compounds that consist only of hydrogen and carbon atoms and are bonded exclusively by single bonds without any cycles...
s are an example of saturated compounds. An unsaturated compound is a chemical compound that contains carbon-carbon double bond
Double bond
A double bond in chemistry is a chemical bond between two chemical elements involving four bonding electrons instead of the usual two. The most common double bond, that between two carbon atoms, can be found in alkenes. Many types of double bonds between two different elements exist, for example in...
s or triple bond
Triple bond
A triple bond in chemistry is a chemical bond between two chemical elements involving six bonding electrons instead of the usual two in a covalent single bond. The most common triple bond, that between two carbon atoms, can be found in alkynes. Other functional groups containing a triple bond are...
s, such as those found in alkene
Alkene
In organic chemistry, an alkene, olefin, or olefine is an unsaturated chemical compound containing at least one carbon-to-carbon double bond...
s or alkyne
Alkyne
Alkynes are hydrocarbons that have a triple bond between two carbon atoms, with the formula CnH2n-2. Alkynes are traditionally known as acetylenes, although the name acetylene also refers specifically to C2H2, known formally as ethyne using IUPAC nomenclature...
s, respectively. Saturated and unsaturated compounds need not consist only of a carbon atom chain. They can have functional groups, as well. It is in this sense that fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
s are classified as saturated
Saturated fat
Saturated fat is fat that consists of triglycerides containing only saturated fatty acids. Saturated fatty acids have no double bonds between the individual carbon atoms of the fatty acid chain. That is, the chain of carbon atoms is fully "saturated" with hydrogen atoms...
or unsaturated
Unsaturated fat
An unsaturated fat is a fat or fatty acid in which there is at least one double bond within the fatty acid chain. A fat molecule is monounsaturated if it contains one double bond, and polyunsaturated if it contains more than one double bond. Where double bonds are formed, hydrogen atoms are...
. The amount of unsaturation of a fatty acid can be determined by finding its iodine number
Iodine number
The iodine value in chemistry is the mass of iodine in grams that is consumed by 100 grams of a chemical substance. An iodine solution is yellow/brown in color and any chemical group in the substance that reacts with iodine will make the color disappear at a precise concentration...
.
In a chain of carbons, such as a fatty acid
Fatty acid
In chemistry, especially biochemistry, a fatty acid is a carboxylic acid with a long unbranched aliphatic tail , which is either saturated or unsaturated. Most naturally occurring fatty acids have a chain of an even number of carbon atoms, from 4 to 28. Fatty acids are usually derived from...
, a double or triple bond will cause a kink in the chain. These kinks have macro-structural implications. Unsaturated fats tend to be liquid
Liquid
Liquid is one of the three classical states of matter . Like a gas, a liquid is able to flow and take the shape of a container. Some liquids resist compression, while others can be compressed. Unlike a gas, a liquid does not disperse to fill every space of a container, and maintains a fairly...
at room temperature, rather than solid
Solid
Solid is one of the three classical states of matter . It is characterized by structural rigidity and resistance to changes of shape or volume. Unlike a liquid, a solid object does not flow to take on the shape of its container, nor does it expand to fill the entire volume available to it like a...
, due to the kinks in the chain. The kinks prevent the molecule
Molecule
A molecule is an electrically neutral group of at least two atoms held together by covalent chemical bonds. Molecules are distinguished from ions by their electrical charge...
s from packing closely together to form a solid. These fats are called oil
Oil
An oil is any substance that is liquid at ambient temperatures and does not mix with water but may mix with other oils and organic solvents. This general definition includes vegetable oils, volatile essential oils, petrochemical oils, and synthetic oils....
s and are present in fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
and plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...
s.
In other unsaturated hydrocarbon
Hydrocarbon
In organic chemistry, a hydrocarbon is an organic compound consisting entirely of hydrogen and carbon. Hydrocarbons from which one hydrogen atom has been removed are functional groups, called hydrocarbyls....
s, the double bond between two carbons prevents rotation of the atom
Atom
The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...
s about the bond, locking them into specific structural formations. When attached atoms occupy similar positions on each carbon, they are referred to as "cis", and when they are on opposite sides, they are called "trans". Most natural hydrocarbons exist in the cis state, but artificially manufactured hydrocarbons are trans. The body lacks the enzyme
Enzyme
Enzymes are proteins that catalyze chemical reactions. In enzymatic reactions, the molecules at the beginning of the process, called substrates, are converted into different molecules, called products. Almost all chemical reactions in a biological cell need enzymes in order to occur at rates...
s to properly break down the trans configuration. This is why trans fats are viewed as dangerous and unhealthy, as they tend to build up. Unsaturated compounds of the two formations are classified as geometric isomers of one another.