A saturated compound is a

chemical compound A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...

(or ion) that resists

addition reaction In organic chemistry, an addition reaction is an organic reaction in which two or more molecule A molecule is a group of two or more atoms that are held together by Force, attractive forces known as chemical bonds; depending on context, ...

s, such as

hydrogenation Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to redox, reduce or Saturated ...

, oxidative addition, and the binding of a Lewis base. The term is used in many contexts and classes of chemical compounds. Overall, saturated compounds are less reactive than unsaturated compounds. Saturation is derived from the Latin word ''saturare'', meaning 'to fill'.An unsaturated compound is also a

(or ion) that attracts reduction reactions, such as dehydrogenation, oxidative reduction

Organic chemistry

Generally distinct types of unsaturated organic compounds are recognized. For hydrocarbons: *

alkene In organic chemistry, an alkene, or olefin, is a hydrocarbon containing a carbon–carbon double bond. The double bond may be internal or at the terminal position. Terminal alkenes are also known as Alpha-olefin, α-olefins. The Internationa ...

(unsaturated) vs alkane (saturated) *

alkyne \ce \ce Acetylene \ce \ce \ce Propyne \ce \ce \ce \ce 1-Butyne In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon—carbon triple bond. The simplest acyclic alkynes with only one triple bond and n ...

(unsaturated) vs alkane (saturated) *

arene Aromatic compounds or arenes are organic compounds "with a chemistry typified by benzene" and "cyclically conjugated." The word "aromatic" originates from the past grouping of molecules based on odor, before their general chemical properties were ...

(unsaturated) vs cycloalkane (saturated) For organic compounds containing heteroatoms (other than C and H), the list of unsaturated groups is long but some common types are: *

carbonyl In organic chemistry, a carbonyl group is a functional group with the formula , composed of a carbon atom double bond, double-bonded to an oxygen atom, and it is divalent at the C atom. It is common to several classes of organic compounds (such a ...

, e.g.

ketone In organic chemistry, a ketone is an organic compound with the structure , where R and R' can be a variety of carbon-containing substituents. Ketones contain a carbonyl group (a carbon-oxygen double bond C=O). The simplest ketone is acetone ( ...

aldehyde In organic chemistry, an aldehyde () (lat. ''al''cohol ''dehyd''rogenatum, dehydrogenated alcohol) is an organic compound containing a functional group with the structure . The functional group itself (without the "R" side chain) can be referred ...

ester In chemistry, an ester is a compound derived from an acid (either organic or inorganic) in which the hydrogen atom (H) of at least one acidic hydroxyl group () of that acid is replaced by an organyl group (R). These compounds contain a distin ...

carboxylic acid In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an Substituent, R-group. The general formula of a carboxylic acid is often written as or , sometimes as with R referring to an organyl ...

s (unsaturated) vs alcohol or ether (saturated) *

nitrile In organic chemistry, a nitrile is any organic compound that has a functional group. The name of the compound is composed of a base, which includes the carbon of the , suffixed with "nitrile", so for example is called " propionitrile" (or pr ...

(unsaturated) vs amine (saturated) *

nitro Nitro may refer to: Chemistry *Nitrogen, a chemical element and a gas except at very low temperatures, with which many compounds are formed: **Nitro compound, an organic compound containing one or more nitro functional groups, -NO2 **Nitro ligand ...

(unsaturated) vs amine (saturated) Unsaturated compounds generally carry out typical addition reactions that are not possible with saturated compounds such as alkanes. A saturated organic compound has only single bonds between carbon atoms. An important class of saturated compounds are the

alkane In organic chemistry, an alkane, or paraffin (a historical trivial name that also has other meanings), is an acyclic saturated hydrocarbon. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree structure in whi ...

s. Many saturated compounds have functional groups, e.g.,

alcohols In chemistry, an alcohol (), is a type of organic compound that carries at least one hydroxyl () functional group bound to a Saturated and unsaturated compounds, saturated carbon atom. Alcohols range from the simple, like methanol and ethanol ...

Unsaturated organic compounds

The concept of saturation can be described using various naming systems,

formula In science, a formula is a concise way of expressing information symbolically, as in a mathematical formula or a ''chemical formula''. The informal use of the term ''formula'' in science refers to the general construct of a relationship betwe ...

s, and analytical tests. For instance,

IUPAC nomenclature IUPAC nomenclature is a set of recommendations for naming chemical compounds and for describing chemistry and biochemistry in general. The International Union of Pure and Applied Chemistry (IUPAC) is the international authority on chemical nomenc ...

is a system of naming conventions used to describe the type and location of unsaturation within organic compounds. The " degree of unsaturation" is a

used to summarize and diagram the amount of hydrogen that a compound can bind. Unsaturation can be determined by

NMR Nuclear magnetic resonance (NMR) is a physical phenomenon in which atomic nucleus, nuclei in a strong constant magnetic field are disturbed by a weak oscillating magnetic field (in the near and far field, near field) and respond by producing ...

mass spectrometry Mass spectrometry (MS) is an analytical technique that is used to measure the mass-to-charge ratio of ions. The results are presented as a ''mass spectrum'', a plot of intensity as a function of the mass-to-charge ratio. Mass spectrometry is used ...

, and

IR spectroscopy Infrared spectroscopy (IR spectroscopy or vibrational spectroscopy) is the measurement of the interaction of infrared radiation with matter by absorption, emission, or reflection. It is used to study and identify chemical substances or functio ...

, or by determining a compound's bromine number or iodine number.

Fatty acids and fats

The terms saturated vs unsaturated are often applied to the

fatty acid In chemistry, in particular in biochemistry, a fatty acid is a carboxylic acid with an aliphatic chain, which is either saturated and unsaturated compounds#Organic chemistry, saturated or unsaturated. Most naturally occurring fatty acids have an ...

constituents of

fat In nutrition science, nutrition, biology, and chemistry, fat usually means any ester of fatty acids, or a mixture of such chemical compound, compounds, most commonly those that occur in living beings or in food. The term often refers specif ...

s. The triglycerides (fats) that comprise

tallow Tallow is a rendered form of beef or mutton suet, primarily made up of triglycerides. In industry, tallow is not strictly defined as beef or mutton suet. In this context, tallow is animal fat that conforms to certain technical criteria, inc ...

are derived from the saturated stearic and monounsaturated

oleic acid Oleic acid is a fatty acid that occurs naturally in various animal and vegetable fats and oils. It is an odorless, colorless oil, although commercial samples may be yellowish due to the presence of impurities. In chemical terms, oleic acid is cl ...

s. Many

vegetable oil Vegetable oils, or vegetable fats, are oils extracted from seeds or from other parts of edible plants. Like animal fats, vegetable fats are ''mixtures'' of triglycerides. Soybean oil, grape seed oil, and cocoa butter are examples of seed ...

s contain fatty acids with one (''monounsaturated'') or more (''polyunsaturated'') double bonds in them.

Saturated and unsaturated compounds beyond organic chemistry

Organometallic chemistry

organometallic chemistry Organometallic chemistry is the study of organometallic compounds, chemical compounds containing at least one chemical bond between a carbon atom of an organic molecule and a metal, including alkali, alkaline earth, and transition metals, and so ...

, a coordinatively unsaturated complex has fewer than 18 valence electrons and thus is susceptible to oxidative addition or coordination of an additional

ligand In coordination chemistry, a ligand is an ion or molecule with a functional group that binds to a central metal atom to form a coordination complex. The bonding with the metal generally involves formal donation of one or more of the ligand's el ...

. Unsaturation is the characteristic of many

catalysts Catalysis () is the increase in reaction rate, rate of a chemical reaction due to an added substance known as a catalyst (). Catalysts are not consumed by the reaction and remain unchanged after it. If the reaction is rapid and the catalyst ...

. The opposite of coordinatively unsaturated is coordinatively saturated. Complexes that are coordinatively saturated rarely exhibit catalytic properties.

Surfaces

physical chemistry Physical chemistry is the study of macroscopic and microscopic phenomena in chemical systems in terms of the principles, practices, and concepts of physics such as motion, energy, force, time, thermodynamics, quantum chemistry, statistical mech ...

, when referring to surface processes, saturation denotes the degree at which a binding site is fully occupied. For example,

base saturation Cation-exchange capacity (CEC) is a measure of how many cations can be retained on soil particle surfaces. Negative charges on the surfaces of soil particles bind positively-charged atoms or molecules (cations), but allow these to exchange with ot ...

refers to the fraction of exchangeable cations that are base cations.

References

{{reflist Organic chemistry Chemical nomenclature