Regional-scale air quality models should include chemical preprocessing of biogenic hydrocarbons before they are emitted to the full regional modeling grid in order to accurately represent the photochemical production of pollutants on the wider scale. Fuentes received support from the University of Virginia to carry out the field research of this study. Fuentes also received support from the U. National Science foundation grant ATM James Kathilankal of the University of Virginia provided assistance to perform the air parcel trajectory analyses. Kell Wilson from the Atmospheric and Turbulence Diffusion Laboratory, National Oceanic and Atmospheric Administration is thanked for sharing the meteorological data included in this manuscript.
Steve Hoskins provided assisted with the field studies. Two anonymous journal reviewers are acknowledged for providing excellent comments to improve the manuscript. Skip to main content.
25.2: Introduction to Hydrocarbons
Advertisement Hide. Article First Online: 08 December This is a preview of subscription content, log in to check access. Acknowledgments Fuentes received support from the University of Virginia to carry out the field research of this study. Atkinson, R. Baldocchi, D. Boundary-Layer Meteor. Calvert, J. Oxford University Press Google Scholar.
- The Diary of Jack the Ripper. The Chilling Confessions of James Maybrick.
- Aliphatic Hydrocarbon - Chemistry Definition.
- Cerium photocatalysis conquers light hydrocarbon chemistry.
- Act Exam Success in Only 6 Simple Steps!.
- Hydrocarbon structures and functional groups.
- Growing your Business: A Handbook for Ambitious Owner-Managers;
Chameides, W. Science , — CrossRef Google Scholar. Finlayson-Pitts, B. Fitzjarrald, D. Climate 14 , — CrossRef Google Scholar. Forkel, R. Foster, D.
Fuentes, J. Fujita, E. Air Waste Manage. Gao, W. Geiger, H. Geron, C. Gill, K. The compound 2—methylpropane has a branched chain the carbon atom in the center of the Lewis structure is bonded to three other carbon atoms. Identifying isomers from Lewis structures is not as easy as it looks. Lewis structures that look different may actually represent the same isomers.
For example, the three structures in Figure 3 all represent the same molecule, n -butane, and hence are not different isomers. They are identical because each contains an unbranched chain of four carbon atoms. The International Union of Pure and Applied Chemistry IUPAC has devised a system of nomenclature that begins with the names of the alkanes and can be adjusted from there to account for more complicated structures.
The nomenclature for alkanes is based on two rules:. When more than one substituent is present, either on the same carbon atom or on different carbon atoms, the substituents are listed alphabetically. Because the carbon atom numbering begins at the end closest to a substituent, the longest chain of carbon atoms is numbered in such a way as to produce the lowest number for the substituents. The ending -o replaces -ide at the end of the name of an electronegative substituent in ionic compounds, the negatively charged ion ends with -ide like chloride; in organic compounds, such atoms are treated as substituents and the -o ending is used.
The number of substituents of the same type is indicated by the prefixes di- two , tri- three , tetra- four , and so on for example, difluoro- indicates two fluoride substituents. Naming Halogen-substituted Alkanes Name the molecule whose structure is shown here:. The four-carbon chain is numbered from the end with the chlorine atom. This puts the substituents on positions 1 and 2 numbering from the other end would put the substituents on positions 3 and 4.
Four carbon atoms means that the base name of this compound will be butane. The bromine at position 2 will be described by adding 2-bromo-; this will come at the beginning of the name, since bromo- comes before chloro- alphabetically.
- Assessment, Learning and Judgement in Higher Education.
- Jefferson’s Welding Encyclopedia.
- Biogenic Hydrocarbon Chemistry within and Above a Mixed Deciduous Forest?
- Homologous series!
The chlorine at position 1 will be described by adding 1-chloro-, resulting in the name of the molecule being 2-bromochlorobutane. Check Your Learning Name the following molecule:. We call a substituent that contains one less hydrogen than the corresponding alkane an alkyl group. The name of an alkyl group is obtained by dropping the suffix -ane of the alkane name and adding -yl :.
The open bonds in the methyl and ethyl groups indicate that these alkyl groups are bonded to another atom. Naming Substituted Alkanes Name the molecule whose structure is shown here:. Solution The longest carbon chain runs horizontally across the page and contains six carbon atoms this makes the base of the name hexane, but we will also need to incorporate the name of the branch.
In this case, we want to number from right to left as shown by the blue numbers so the branch is connected to carbon 3 imagine the numbers from left to right—this would put the branch on carbon 4, violating our rules.
The branch attached to position 3 of our chain contains two carbon atoms numbered in red —so we take our name for two carbons eth- and attach -yl at the end to signify we are describing a branch. Putting all the pieces together, this molecule is 3-ethylhexane. This diversity of possible alkyl groups can be identified in the following way: The four hydrogen atoms in a methane molecule are equivalent; they all have the same environment.
They are equivalent because each is bonded to a carbon atom the same carbon atom that is bonded to three hydrogen atoms. It may be easier to see the equivalency in the ball and stick models in Figure 1. Removal of any one of the four hydrogen atoms from methane forms a methyl group. Likewise, the six hydrogen atoms in ethane are equivalent Figure 1 and removing any one of these hydrogen atoms produces an ethyl group.
Each of the six hydrogen atoms is bonded to a carbon atom that is bonded to two other hydrogen atoms and a carbon atom. However, in both propane and 2—methylpropane, there are hydrogen atoms in two different environments, distinguished by the adjacent atoms or groups of atoms:. Each of the six equivalent hydrogen atoms of the first type in propane and each of the nine equivalent hydrogen atoms of that type in 2-methylpropane all shown in black are bonded to a carbon atom that is bonded to only one other carbon atom.
The two purple hydrogen atoms in propane are of a second type. They differ from the six hydrogen atoms of the first type in that they are bonded to a carbon atom bonded to two other carbon atoms. The green hydrogen atom in 2-methylpropane differs from the other nine hydrogen atoms in that molecule and from the purple hydrogen atoms in propane.
- Petroleum - Chemistry - Hydrocarbons.
- Biogenic Hydrocarbon Chemistry within and Above a Mixed Deciduous Forest | SpringerLink.
- Proceedings of the FISITA 2012 World Automotive Congress: Volume 6: Vehicle Electronics;
- Isomers of Alkenes.
- Class Definition for Class - CHEMISTRY OF HYDROCARBON COMPOUNDS!
- Homologous series - Revision 1 - National 5 Chemistry - BBC Bitesize.
The green hydrogen atom in 2-methylpropane is bonded to a carbon atom bonded to three other carbon atoms. Two different alkyl groups can be formed from each of these molecules, depending on which hydrogen atom is removed.
The names and structures of these and several other alkyl groups are listed in Figure 4. Note that alkyl groups do not exist as stable independent entities. They are always a part of some larger molecule. The location of an alkyl group on a hydrocarbon chain is indicated in the same way as any other substituent:. Alkanes are relatively stable molecules, but heat or light will activate reactions that involve the breaking of C—H or C—C single bonds.
Combustion is one such reaction:.
Alkanes burn in the presence of oxygen, a highly exothermic oxidation-reduction reaction that produces carbon dioxide and water. As a consequence, alkanes are excellent fuels. For example, methane, CH 4 , is the principal component of natural gas. Butane, C 4 H 10 , used in camping stoves and lighters is an alkane. Gasoline is a liquid mixture of continuous- and branched-chain alkanes, each containing from five to nine carbon atoms, plus various additives to improve its performance as a fuel.
Kerosene, diesel oil, and fuel oil are primarily mixtures of alkanes with higher molecular masses. The main source of these liquid alkane fuels is crude oil, a complex mixture that is separated by fractional distillation. Fractional distillation takes advantage of differences in the boiling points of the components of the mixture see Figure 5.
You may recall that boiling point is a function of intermolecular interactions, which was discussed in the chapter on solutions and colloids. No carbon-carbon bonds are broken in these reactions, and the hybridization of the carbon atoms does not change.
For example, the reaction between ethane and molecular chlorine depicted here is a substitution reaction:. The C—Cl portion of the chloroethane molecule is an example of a functional group , the part or moiety of a molecule that imparts a specific chemical reactivity. The types of functional groups present in an organic molecule are major determinants of its chemical properties and are used as a means of classifying organic compounds as detailed in the remaining sections of this chapter.
Want more practice naming alkanes? Watch this brief video tutorial to review the nomenclature process. Organic compounds that contain one or more double or triple bonds between carbon atoms are described as unsaturated. You have likely heard of unsaturated fats.
Related Hydrocarbon Chemistry
Copyright 2019 - All Right Reserved