What is the difference between a hydrocarbon and an alkane

Chloroform vapor is a anesthetic: James Young Simpson was the first to use chloroform as an anesthetic during childbirth in presumably, not on himself!

However, since chloroform is carcinogenic, and toxic to the liver, it is not widely used for this purpose anymore. It's also useful for knocking out giant apes. Tetrachloromethane Carbon Tetrachloride 3D Download 3D Tetrachloromethane better known as carbon tetrachloride is a liquid at room temperature, with a density of 1. It used to be a common organic solvent, and was widely used for dry cleaning and spot removal.

However, it has been shown to be toxic and carcinogenic, so other solvents are used instead. Carbon tetrachloride is also a contributor to ozone depletion see Freon , and has been banned under the Montreal Protocols that set strict limits on the use of CFCs. It was heavily used in dry cleaning, but it has been replaced by other solvents such as tetrachloroethylene under the Montreal Protocols see Freon Dichlorodifluoromethane Freon 3D Download 3D Dichlorodifluoromethane Freon is an example of the chlorofluorocarbons CFCs, or freons , which are organic compound containing fluorine and chlorine atoms.

These compounds were developed in the s for use as refrigerants; prior to this, ammonia was used as a refrigerant, but the high toxicity of ammonia gas made this less than ideal. The CFCs are relatively nontoxic, very unreactive, and boil at low temperatures, and were thus ideal for use in refrigeration equipment. In addition, CFCs were widely used as aerosol propellants in spray cans, and as foaming agents in the manufacture of plastic foams such as Styrofoam.

Unfortunately, the low reactivity of the CFCs leads to a major environmental problem: they persist in the environment for a long time up to a century , and eventually make their way into the upper atmosphere, where they damage the ozone layer. Ozone , O 3 , is an allotropic form of molecular oxygen, O 2 , which is found in the stratosphere, at an altitude of 10 to 50 km above the surface of the Earth. It is produced when photons h n of high-energy ultraviolet light wavelengths of nm or less from the Sun splits oxygen molecules into oxygen atoms O.

The oxygen atoms combine with oxygen molecules to make ozone:. This ozone that is produced from this reaction absorbs ultraviolet light with wavelengths of nm or less, splitting into oxygen molecules and oxygen atoms,.

The ozone in the ozone layer thus protects the surface of the Earth and more importantly, the living organisms that make their home there from much of the damaging high-energy ultraviolet light from the Sun. When a molecule of Freon drifts into the upper atmosphere, photons of high-energy light can strike it, causing it to release a chlorine atom:. The chlorine atom has an unpaired electron, and is a highly reactive free radical , which reacts with ozone in the stratosphere, converting it to molecular oxygen:.

The chlorine atom is regenerated in this process, and behaves as a catalyst; one chlorine atom can destroy up to , ozone molecules. The mechanism for ozone destruction was first published in by F. Sherwood Rowland and Mario J. Molina; they shared the Nobel Prize in Chemistry in with Paul Crutzen, who proposed a similar mechanism for the destruction of ozone by nitrogen oxides in In , an international agreement called the Montreal Protocol on Substances that Deplete the Ozone Layer was signed.

This treaty cut back on the production and use of CFCs; in , partially in response to the alarming increase in the size of the "ozone hole" over the South Pole, the agreement was extended to become a ban on the use of CFCs starting in It is believed that CFC levels in the stratosphere will continue to rise through the s, and will not return to safe levels until the middle of the s.

CFCs in refrigeration are being replaced by hydrochlorofluorocarbons HCFCs , which are slightly more reactive than CFCs, and fall apart before reaching the stratosphere, and by hydrofluorocarbons HFCs ; in propellants they are being replaced mostly by carbon dioxide and low-boiling point hydrocarbons. The HCFCs are not fully halogenated — i. Because of this, these molecules are less stable than the CFCs, and degrade to a larger extent before they reach the upper atmosphere.

The HFCs contain only hydrogen, fluorine, and carbon, and are not damaging to the ozone layer. Freona is now widely used in the air conditioning systems of automobiles in place of Freon Download 3D Bromochlorodifluoromethane Halon is an example of a halon , a haloalkane that has bromine atoms in addition to chlorine and fluorine atoms.

Halons are very stable, and are useful in fire extinguishers, since they do not damage electronic equipment. Their use has largely been phased out under the Montreal Protocols see Freon above , but they are still used in fire suppression systems aboard some aircraft, since no completely satisfactory and safe alternatives have been discovered. Dichlorodiphenyltrichloroethane DDT 3D Download 3D Dichlorodiphenyltrichloroethane , or 1,1,1-trichloro-2,2-bis- p -chlorophenyl ethane , better knows as DDT , is an very powerful insecticide.

It was unique among the known insecticides at the time of its discovery in , in that it was effective against insects, but not very toxic to mammals. DDT was widely used to kill mosquitoes that spread malaria, and was also effective against the insects that spread sleeping sickness and typhus. Unfortunately, DDT persists in the environment for a long time, and its accumulation in wildlife lead to decreases in the populations of several bird species. It is used in some shampoos to kill lice and other ectoparasites.

However, it is a suspected carcinogen, and is banned in California, and several countries. Chlordane 3D Download 3D Chlordane was used as a pesticide on some crops, and was also used to kill termites. Because of concerns about its toxicity, it was banned by the EPA in Atkins, Molecules , 2nd ed. Cambridge: Cambridge University Press, , p. Paula Yurkanis Bruice, Organic Chemistry , 4th ed.

Upper Saddle River: Prentice Hall, , p. Marye Anne Fox and James K. Whitesell, Organic Chemistry , 3rd ed. Sudbury: Jones and Bartlett Publishers, p.

Maitland Jones, Jr. New York: W. Richard J. Lewis, Sr. New York: Van Nostrand Reinhold, Marc Loudon, Organic Chemistry , 4th ed. New York: Oxford University Press, , p. Englewood Cliffs: Prentice Hall, , p.

Sharp, The Penguin Dictionary of Chemistry , 2nd ed. London: Penguin Books, Truman Schwartz, Diane M. Bunce, Robert G. Silberman, Conrad L.

Stanitski, Wilmer J. Stratton, and Arden P. Dubuque: Wm. Brown Communicatiions, Inc. Wade, Jr. Martha Windholz ed. Number of Carbons Stem 1 meth- 2 eth- 3 prop- 4 but- 5 pent- 6 hex- 7 hept- 8 oct- 9 non- 10 dec-.

There are five structural isomers of C 6 H 14 : Using common or non-systematic names is not practical for molecules with a large number of carbon atoms, since it would be necessary to memorize unique names for each possible compound.

Table 1. This molecule is often found on traffic signs: well, maybe not Cyclononane C 9 H 18 3D Download 3D Cyclononane is a ring of nine carbon atoms. The oxygen atoms combine with oxygen molecules to make ozone: This ozone that is produced from this reaction absorbs ultraviolet light with wavelengths of nm or less, splitting into oxygen molecules and oxygen atoms, which then re-combine to form ozone, which can absorb another photon of ultraviolet light.

When a molecule of Freon drifts into the upper atmosphere, photons of high-energy light can strike it, causing it to release a chlorine atom: The chlorine atom has an unpaired electron, and is a highly reactive free radical , which reacts with ozone in the stratosphere, converting it to molecular oxygen: The chlorine atom is regenerated in this process, and behaves as a catalyst; one chlorine atom can destroy up to , ozone molecules.

This double bond is composed of a sigma bond and a pi bond. This pi bond can be broken down; this is called the opening up of the double bond. Then electrophiles can be attached to these carbon atoms that was in a double bond.

These are called addition reaction s of alkenes. In addition, polymerization is a major reaction that alkenes are able to undergo. The opening up of the double bond allows alkenes to undergo polymerization. Here, one alkene molecule is called a monomer. This leads to the production of very important polymers.

Alkenes show geometrical isomerism. This is also called cis-trans isomerism. When naming an alkene, one should also consider the cis-trans geometry of these molecules. Alkenes: Alkenes are unsaturated hydrocarbons having the chemical formula C n H 2n. Alkanes: Alkanes are composed of only single bonds.

Alkenes: Alkenes are composed of double bonds as well as single bonds. Alkenes: The chemical formula for alkenes is C n H 2n. Alkanes: Alkanes cannot undergo polymerization.

Alkenes: Alkenes can undergo polymerization. Alkanes and alkenes are important hydrocarbons. Although there are similarities between alkanes and alkenes such as nonpolar behavior and insolubility in water, they have many distinct features.

Accessed 21 Aug. Her interest areas for writing and research include Biochemistry and Environmental Chemistry. View all posts. Leave a Reply Cancel reply. The alkanes are a subset of hydrocarbons whose names all end in —ane. The names, molecular formulae and the structural formulae of the first eight alkanes must be learned. Using a mnemonic can make learning the names easier.

Alkanes contain more than double the number of hydrogen atoms than carbon atoms. To calculate how many hydrogen atoms an alkane has, double the number of carbons and add two. The second subset of hydrocarbons is called the alkenes.