Isomer in the context of Hexene

Butanol (also called butyl alcohol) is a four-carbon alcohol with a formula of C₄H₉OH, which occurs in five isomeric structures (four structural isomers), from a straight-chain primary alcohol to a branched-chain tertiary alcohol; all are a butyl or isobutyl group linked to a hydroxyl group (sometimes represented as BuOH, sec-BuOH, i-BuOH, and t-BuOH). These are 1-butanol, two stereoisomers of sec-butyl alcohol, isobutanol and tert-butyl alcohol. Butanol is primarily used as a solvent and as an intermediate in chemical synthesis, and may be used as a fuel. Biologically produced butanol is called biobutanol, which may be n-butanol or isobutanol.

There are two isomers of propanol.

• 1-Propanol, n-propanol, or propan-1-ol: CH₃CH₂CH₂OH, the most common meaning
• 2-Propanol, isopropyl alcohol, isopropanol, or propan-2-ol: (CH₃)₂CHOH

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 which all the carbon–carbon bonds are single. Alkanes have the general chemical formula C_nH_2n+2. The alkanes range in complexity from the simplest case of methane (CH₄), where n = 1 (sometimes called the parent molecule), to arbitrarily large and complex molecules, like hexacontane (C₆₀H₁₂₂) or 4-methyl-5-(1-methylethyl) octane, an isomer of dodecane (C₁₂H₂₆).

The International Union of Pure and Applied Chemistry (IUPAC) defines alkanes as "acyclic branched or unbranched hydrocarbons having the general formula C_nH_2n+2, and therefore consisting entirely of hydrogen atoms and saturated carbon atoms". However, some sources use the term to denote any saturated hydrocarbon, including those that are either monocyclic (i.e. the cycloalkanes) or polycyclic, despite them having a distinct general formula (e.g. cycloalkanes are C_nH_2n).

Maltose (/ˈmɔːltoʊs/ or /ˈmɔːltoʊz/), also known as maltobiose or malt sugar, is a disaccharide formed from two units of glucose joined with an α(1→4) bond. In the isomer isomaltose, the two glucose molecules are joined with an α(1→6) bond. Maltose is the two-unit member of the amylose homologous series, the key structural motif of starch. When beta-amylase breaks down starch, it removes two glucose units at a time, producing maltose. An example of this reaction is found in germinating seeds, which is why it was named after malt. Unlike sucrose, it is a reducing sugar.

Limonene (/ˈlɪmənˌiːn/) is a colorless liquid aliphatic hydrocarbon classified as a cyclic monoterpene, and is the major component in the essential oil of citrus fruit peels. The (+)-isomer, occurring more commonly in nature as the fragrance of oranges, is a flavoring agent in food manufacturing. It is also used in chemical synthesis as a precursor to carvone and as a renewables-based solvent in cleaning products. The less common (−)-isomer has a piny, turpentine-like odor, and is found in the edible parts of such plants as caraway, dill, and bergamot orange plants.

1-Propanol (also propan-1-ol, propanol, n-propyl alcohol) is a primary alcohol with the formula CH₃CH₂CH₂OH and sometimes represented as PrOH or n-PrOH. It is a colourless liquid and an isomer of 2-propanol. 1-Propanol is used as a solvent in the pharmaceutical industry, mainly for resins and cellulose esters, and, sometimes, as a disinfecting agent.

1-Butanol, also known as butan-1-ol or n-butanol, is a primary alcohol with the chemical formula C₄H₉OH and a linear structure. Isomers of 1-butanol are isobutanol, butan-2-ol and tert-butanol. The unmodified term butanol usually refers to the straight chain isomer.

1-Butanol occurs naturally as a minor product of the ethanol fermentation of sugars and other saccharides and is present in many foods and drinks. It is also a permitted artificial flavorant in the United States, used in butter, cream, fruit, rum, whiskey, ice cream and ices, candy, baked goods, and cordials. It is also used in a wide range of consumer products.

Tetrahydrocannabinol (THC) is a cannabinoid found in cannabis. It is the principal psychoactive constituent of Cannabis and one of at least 113 total cannabinoids identified on the plant. Although the chemical formula for THC (C₂₁H₃₀O₂) describes multiple isomers, the term THC usually refers to the delta-9-THC isomer with chemical name (−)-trans-Δ-tetrahydrocannabinol. It is a colorless oil.

THC, also known pharmaceutically as dronabinol, is used medically to relieve chemotherapy-induced nausea, HIV/AIDS-related anorexia, and symptoms of multiple sclerosis, including neuropathic pain and spasticity. It acts as a partial agonist at CB₁ and CB₂ cannabinoid receptors.

Ethylene oxide is an organic compound with the formula C₂H₄O. It is a cyclic ether and the simplest epoxide: a three-membered ring consisting of one oxygen atom and two carbon atoms. Ethylene oxide is a colorless and flammable gas with a faintly sweet odor. Because it is a strained ring, ethylene oxide easily participates in a number of addition reactions that result in ring-opening. Ethylene oxide is isomeric with acetaldehyde and with vinyl alcohol. Ethylene oxide is industrially produced by oxidation of ethylene in the presence of a silver catalyst.

Chemical nomenclature is a set of rules to generate systematic names for chemical compounds. The nomenclature used most frequently worldwide is the one created and developed by the International Union of Pure and Applied Chemistry (IUPAC).

IUPAC Nomenclature ensures that each compound (and its various isomers) have only one formally accepted name known as the systematic IUPAC name. However, some compounds may have alternative names that are also accepted, known as the preferred IUPAC name which is generally taken from the common name of that compound. Preferably, the name should also represent the structure or chemistry of a compound.

The structural formula of a chemical compound is a graphic representation of the molecular structure (determined by structural chemistry methods), showing how the atoms are connected to one another. The chemical bonding within the molecule is also shown, either explicitly or implicitly. Unlike other chemical formula types, which have a limited number of symbols and are capable of only limited descriptive power, structural formulas provide a more complete geometric representation of the molecular structure. For example, many chemical compounds exist in different isomeric forms, which have different enantiomeric structures but the same molecular formula. There are multiple types of ways to draw these structural formulas such as: Lewis structures, condensed formulas, skeletal formulas, Newman projections, Cyclohexane conformations, Haworth projections, and Fischer projections.

Several systematic chemical naming formats, as in chemical databases, are used that are equivalent to, and as powerful as, geometric structures. These chemical nomenclature systems include SMILES, InChI and CML. These systematic chemical names can be converted to structural formulas and vice versa, but chemists nearly always describe a chemical reaction or synthesis using structural formulas rather than chemical names, because the structural formulas allow the chemist to visualize the molecules and the structural changes that occur in them during chemical reactions. ChemSketch and ChemDraw are popular downloads/websites that allow users to draw reactions and structural formulas, typically in the Lewis Structure style.

In chemistry and physics, metastability is an intermediate energetic state within a dynamical system other than the system's state of least energy.A ball resting in a hollow on a slope is a simple example of metastability. If the ball is only slightly pushed, it will settle back into its hollow, but a stronger push may start the ball rolling down the slope. Bowling pins show similar metastability by either merely wobbling for a moment or tipping over completely. A common example of metastability in science is isomerisation. Higher energy isomers are long lived because they are prevented from rearranging to their preferred ground state by (possibly large) barriers in the potential energy.

During a metastable state of finite lifetime, all state-describing parameters reach and hold stationary values. In isolation:

Butanone, also known as methyl ethyl ketone (MEK) or ethyl methyl ketone, is an organic compound with the formula CH₃C(O)CH₂CH₃. This colorless liquid ketone has a sharp, sweet odor reminiscent of acetone. It is produced industrially on a large scale, but occurs in nature only in trace amounts. It is partially soluble in water, and is commonly used as an industrial solvent. It is an isomer of another solvent, tetrahydrofuran.

In chemistry, an open-chain compound (or open chain compound) or acyclic compound (Greek prefix α 'without' and κύκλος 'cycle') is a compound with a linear structure, rather than a cyclic one.An open-chain compound having no side groups is called a straight-chain compound (also spelled as straight chain compound). Many of the simple molecules of organic chemistry, such as the alkanes and alkenes, have both linear and ring isomers, that is, both acyclic and cyclic. For those with 4 or more carbons, the linear forms can have straight-chain or branched-chain isomers. The lowercase prefix n- denotes the straight-chain isomer; for example, n-butane is straight-chain butane, whereas i-butane is isobutane. Cycloalkanes are isomers of alkenes, not of alkanes, because the ring's closure involves a C-C bond. Having no rings (aromatic or otherwise), all open-chain compounds are aliphatic.

Typically in biochemistry, some isomers are more prevalent than others. For example, in living organisms, the open-chain isomer of glucose usually exists only transiently, in small amounts; D-glucose is the usual isomer; and L-glucose is rare.

Isobutane, also known as i-butane, 2-methylpropane or methylpropane, is a chemical compound with molecular formula HC(CH₃)₃. It is an isomer of butane. Isobutane is a colorless, odorless gas.It is the simplest alkane with a tertiary carbon atom. Isobutane is used as a precursor molecule in the petrochemical industry, for example in the synthesis of isooctane.

Butanol may be used as a fuel in an internal combustion engine. It is more similar to gasoline than it is to ethanol. A C4-hydrocarbon, butanol is a drop-in fuel and thus works in vehicles designed for use with gasoline without modification.Both n-butanol and isobutanol have been studied as possible fuels. Both can be produced from biomass (as "biobutanol" ) as well as from fossil fuels (as "petrobutanol"). The chemical properties depend on the isomer (n-butanol or isobutanol), not on the production method.

In organic chemistry, butyl is a four-carbon alkyl radical or substituent group with general chemical formula −C₄H₉, derived from either of the two isomers (n-butane and isobutane) of butane.

The isomer n-butane can connect in two ways, giving rise to two "-butyl" groups: