The difference between alkanes and alkenes
In organic chemistry, an alkene is an unsaturated hydrocarbon that contains at least one carbon–carbon double bond. The words alkene and olefin are often used interchangeably. Acyclic alkenes, with only one double bond and no other functional groups, known as mono-enes, form a …
ALKANES : ALKENES : ALKYNES : Description : Alkanes are organic compounds that consist entirely of a single-bonded carbon and hydrogen atoms and lack any other functional groups. Alkynes are unsaturated carbon that shares a double bond at the carbon site. Alkynes are unsaturated carbon that shares a triple bond at the carbon site.
Examples of Alkanes include: 1 Methane (CH4) 2 Ethane (C2H6) 3 Propane (C3H8) 4 Butane (C4H10) 5 Pentane (C5H12) 6 Hexane (C6H14)
Alkenes specifically are those unsaturated hydrocarbons which have at least one double bond. They are represented as CnH2n in general when there is no other functional group. They are also called olefin or olefine. Alkenes have the pi bond between the carbon atoms,...
Also, the boiling point of alkynes is slightly higher than those of their corresponding alkenes, due to the one extra bond at the carbon site. Alkynes are generally nonpolar molecules with little solubility in polar solvents, such as water. They are readily soluble in nonpolar solvents such as ether and acetone.
Alkanes have only single bonds between carbon atoms and are called saturated hydrocarbons. Alkenes have at least one carbon-carbon double bond. Alkynes have one or more carbon-carbon triple bonds. Alkenes and alkynes are called as unsaturated hydrocarbons.
Alkenes have double bonds; alkynes have triple bonds. Both undergo addition reactions. No; a triply bonded carbon atom can form only one other bond.
The main differences between alkanes and alkene are their functional groups and degree of unsaturation. Alkanes are known as saturated hydrocarbons. Alkenes are known unsaturated hydrocarbons as it contains a C=C bond in its structure. The C=C is its functional group.
Alkenes and alkynes are unsaturated hydrocarbons with atleast one double bond which is a Π bond, whereas alkanes contain only σ bonds. As σ bonds are stronger than Π bonds, alkanes are less reactive than alkenes and alkynes.
For alkanes suffix '-ane' is used, for alkenes, the suffix '-ene' is used and the suffix 'yne' is used for alkynes. For example, C2H6 is known as ethane, C2H4 is known as ethene and C2H2 is known as ethyne. The parent chain is numbered such that we reach to the double-bonded or triple bonded carbon atom earliest.
Alkanes are saturated hydrocarbons; meaning a single bond between the carbon atoms; alkenes are unsaturated hydrocarbons meaning one or more double bonds between carbon atoms; alkynes are also unsaturated hydrocarbons with one or more triple bonds between the carbon atoms.
The similarity between alkanes, alkenes and alkynes is that they all are hydrocarbons. Alkane is a simple hydrocarbon. It contains C and H atoms.
Alkenes are generally prepared through elimination reactions in which two atoms on adjacent carbon atoms are removed , resulting in the formation of a double bond. Preparations include the dehydration of alcohols, the dehydrogenation of alkyl halides and the dehalogenation of alkanes.
Alkanes are organic compounds that consist entirely of single-bonded carbon and hydrogen atoms and lack any other functional groups. In other words, an alkane consists of hydrogen and carbon atoms arranged in a tree like structure in which all the carbon-carbon bonds are single. Alkanes have the general formula CnH2n+2 and can be subdivided ...
Hydrocarbons are compounds that are made up of atoms of carbon and hydrogen exclusively. The unique nature of the carbon ensures that it shares a strong covalent bond with hydrogen. Since carbon atoms will make long chains with relative ease, hydrocarbons can be very big molecules linking even hundreds of atoms.
Alkanes have the general formula CnH2n+2. For example, an alkane with 2 (n) carbon atoms, will have 6 (2n+2) hydrogen atoms. Their adjacent atoms are connected with sigma bonds and form tetrahedral centers around the carbon atoms. As these bonds are all single bonds, there is free rotation around all connections.
Each carbon atom has four bonds (either C-H or C-C) and each hydrogen atom is joined to a carbon atom (H-C bonds). A series of linked carbon atoms is known as the carbon skeleton or carbon backbone. Examples of Alkanes include:
An alkyne is an unsaturated hydrocarbon containing at least one carbon-carbon triple bond. The simplest acyclic alkynes with only one triple bond and no other functional group form a homologous series with the general chemical formula CnH2n-2.
Alkenes generally have stronger smells than their corresponding alkanes. Ethylene has a sweet and musty odor. Alkenes are relatively stable compounds, but are more reactive than alkanes , either because of the reactivity of the carbon-carbon double bond or the presence of allylic CH centers.
Both alkenes and alkynes are hydrocarbons having carbon and hydrogen atoms. There can be other substituents attached to these molecules instead of hydrogens. Therefore, large numbers of molecules are possible. Due to multiple bonds, they can polymerize and make larger chains. Thus, they are especially valuable in useful polymer synthesis.
Moreover, the density of alkenes is less than water. These compounds undergo addition reactions due to the double bonds. For example, in the hydrogenation reaction, two hydrogens attached to the double bond and making the alkene to the corresponding alkane. This reaction speeds up in the presence of a metal catalyst.
There, we should number the chain of carbons to give the carbon atoms of the triple bond the lowest possible number . Furthermore, the physical properties of alkynes are similar to the corresponding alkanes. Usually, the alkynes having low molecular weights are in the gaseous form at room temperature.
Hydrocarbon molecules with carbon-carbon triple bond are alkynes. The common name for this family is acetylenes. Ethylene is the simplest molecule in this family with two carbons and two hydrogens. It has the molecular formula of C 2 H 2 and following is its structure.
Ethene is the simplest alkene molecule, having two carbons and four hydrogens. It has one carbon-carbon double bond, and the molecular formula is C 2 H 4. The chemical structure of this molecule is as follows: H2C = CH2. When naming the alkenes, we use the suffix “ene” instead of “ane” at the end of the name of an alkane.
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When naming the alkenes, we use the suffix “ene” instead of “ane” at the end of the name of an alkane. We should take the longest carbon chain containing the double bond and should number it in a way, to give the minimum number to the double bond. The physical properties of alkenes are similar to the corresponding alkanes.