Simple organic compounds containing carbon, hydrocarbons with functional groups
Carbon (C), in most inorganic and organic. Carbon is fairly inert, but at high temperatures to form compounds with metals, hydrogen, oxygen and various. Carbon is the only element with the ability to chain and cyclic compounds of carbon atoms, forming the line-up next to each other in various lengths. This makes the carbon-based organic chemistry. With carbonmore than 10 million known organisms survive, even thrive, on this earth. In addition, there are about 200,000 known inorganic compounds that contain carbon.
Carbon is an important rock minerals to form carbonates. Since carbon dioxide (CO2), can be dissolved in water and is also found in the atmosphere. This is an important component of all plants and animals, all living organisms. Those organisms that have died in the early history of our planet have helped create a hugeSupply of coal and carbon-based fossil fuels such as coal, oil and natural gas.
Organic material containing carbon, its atoms are simple, single bonds (saturated compounds) or in double and triple bonds connected (unsaturated compounds). Carbon chains are the result. The sites that are not used for the carbon-carbon bond, for bonds with hydrogen (hydrocarbons), or used with other elements.
Depending on the nature of the carbon chain is present, we candistinguish between compounds with open chains (linear or branched - aliphatic or acyclic) and cyclic compounds. Aliphatic compounds are classified in the ranks of branched carbon-containing compounds. Cyclic carbon-containing compounds are distinguished by their carbon atoms arranged in a circle by a closed circuit. Of these, the most important aroma compounds of carbon, from the founding member of the aromatics, benzene (C6H6). In it, the carbon atoms form aCircuit along with the individual bonds with each show, both single and double bond character, a sort of hybrid between the two. Some of the most important organic compounds are fats, proteins and hydrocarbons.
Hydrocarbons
Hydrocarbons are composed exclusively of carbon and hydrogen. They are the simplest of all organic compounds. There are three types of homologous families of hydrocarbons: alkanes, alkenes and alkynes. Alkanes contain only single bonds betweenCarbon atoms. Alkenes contain at least one double bond. Alkynes contain at least one triple bond. Most of these types of hydrocarbons may exist with the same chemical formula in another form or chemical structure. If a compound has the same chemical formula, but it has two possible structures, these structures are called isomers.
Hydrocarbon molecules may also contain what are called functional groups. These are groups that at least one carbon atom that contain hydrogen or not.These functional groups can influence the chemical behavior of the molecule that contains, in particular by the chemical molecules. An example is ethanol - CH3CH2OH. Here is the functional group-OH, with the determination of oxygen.
Stereochemistry
Stereochemistry is simply the three-dimensional arrangement of a molecule. Organic molecules have the same chemical formula can be organized in a different way their atoms in space. If they do, often have significantlydifferent chemical properties.
Isomers, these types of compounds that have the same chemical formula but different atomic arrangements in the room. Isomers can be classified as structural isomers and stereoisomers.
Stereoisometric molecules change their atomic arrangement as a result of changes in pressure or temperature. All types of loans and bonds (single, double, triple) are likewise preserved the original, however.
Structural isomers have atoms that change theirLocation in a molecule. An example is a linear combination (in which all the carbon atoms fed in a linear fashion), compared to the same chemical formula associated with a linear structure and shorter branches (chain isomerism). Functional groups may change their position (functional isomerism), or differ from each other isomer in the position of a double or triple bond (bond isomerism).
The number of carbon atoms is determined by a hydrocarbon, which can take many forms, including wireless. TheNumber of possible isomers increases in a compound, the number of carbon atoms that contains increases.
Alkanes, alkenes, alkynes
Hydrocarbons are composed entirely of hydrogen and oxygen. There are three types of homogeneous hydrocarbons (whose members differ by one CH2): alkanes, alkenes and alkynes. The difference between these three groups is the link between the types of carbon. Alkanes only form single bonds, double bonds are alkenes and alkynes there at least one triple bondBond.
The simplest alkane is methane. It 'consists of a carbon atom that is bonded to four hydrogen atoms. When a CH 2 group is added, the mixture second alkane is formed. The naming of alkanes, like all other hydrocarbons is based on the rules of the IUPAC (International Union of Pure and Applied Chemistry). Alcano all the names end with-ane (alkane). Before this term is a prefix that the amount of carbon atoms, corresponding to describe either a greek or latinNumber. The first four alkanes are named after the historic conference.
Methane: CH4, ethane C2H6, C3H8 propane, butane, C4H10, C5H12 pentane. The formula of alkanes can be calculated using the simple formula CnH2n +2. The number of carbon atoms is the decisive factor, which is what alkane. Alkanes, no matter how many carbon atoms they contain all share some common characteristics. For example, it is typical for all alkanes, which are not very reactive,Burn well, and react in a similar manner with the halogens in the photochemical reactions of substitution (exchange reactions). With increasing size of the molecule in the family alkane, alkanes differ from each other in a fundamental way. The first four alkanes are gaseous state of matter. Alkanes with 5-16 carbon atoms and are liquid alkanes with 17 or more carbon atoms are solid. Boiling and melting point increase with increasing atomic number.
Branched alkanes arefirst by the amount of carbon atoms contain called in a row. If a radical is contained in an alkaline compound, the end-ane is replaced by-a. The branch must be identified in any way, so that its position to determine exactly the main carbon chain. For this reason, the carbon atoms are, from left to right from the lowest number the largest number such that the branch is arbitrarily assigned the lowest number possible. The main chain is the longest in the molecule. Ifdifferent chains of the molecule, they are assigned to the letters of the alphabet.
Properties and reactivity
The bond between carbon and hydrogen in an alkane molecule is a weak polar atomic bonds. For this reason, the individual atoms of alkanes contribute only a very weak partial loads. These partial charges cancel each other out over the molecule, since it is completely symmetrical. The result is a molecule that is non-polar products. This does not mean not one molecule of an alkaneelectrostatically with other atoms like their weak van der Waals forces are intermolecular non-Poplar found between molecules, so that they attract and repel one another so weak. The size of these forces is increasing to an increase in molecular size. According to this idea of modifying the properties of straight chain alkanes with the growing size of the carbon chain.
In temperature, the first four alkanes in gaseous state of matter are located. Pentane is thefirst liquid alkanes. Increase in hexane (16), compounds are always more viscous alkanes (paraffin oil), because the viscosity increases the strength of van der Waals forces. Of heptadecane (17), the solid alkanes (paraffins) are. Their melting and boiling point increase in the number of carbon atoms in their chains.
Alkanes burn easily. When burned, the products are carbon dioxide and water. Chain alkanes with increasing size, given the same amountOxygen to burn less easily, so that carbon soot (elemental carbon) with increasing size of the chain length is formed. In alkane molecules, all bonds are saturated. For this reason, alkanes are not very reactive. They tend to form compounds with halogens.
The van der Waals forces
Because the molecules carry a partial charge, there are strengths and attractions between adjacent molecules. These forces between molecules are very small, but large enough to contain the moleculetogether. The longer the carbon chain of a molecule is to take over the atoms of these respective forces, the greater the appeal arising therefrom. If the internal forces are small in small alkanes, they may not be strong enough to hold together the molecules at room temperature. With increasing size of the carbon chain, but these are increasing intramolecular forces. For the chain length of 17 carbon atoms, the van der Waals forces are so strong that instead of individual molecules together insolid state of matter.
Alkenes
Alkenes (olefins) are unsaturated compounds of carbon with hydrogen, which contain one or two double bonds between carbon atoms. They burn soot and carbon dioxide to form carbon dioxide and water. They are more reactive than alkanes due to the fact that they contain double bonds.
Multiple bonds (double, triple bonds) are energetically less favorable for the atoms that the corresponding single bonds. For this reason, the atoms in a compoundtrying to break more bonds to single bonds, which are cheaper to make energy. This explains why the compounds, the double and triple bonds contain much more reactive than single bonds are included. The alkenes are ethene: propene C2H4: C3H6, C4H8 butene and pentene: C5H10. Up to butene, the alkenes occur in the form of gas. Up to hexadecene (C16H32) are found more liquid alkenes solid state of matter. Their general chemical formulaCnH2n.
Alkynes
Alkynes (acetylenes) are unsaturated hydrocarbons that contain one or more triple bonds necyclical between carbon atoms. When burned, tend to form carbon soot. It is the presence of oxygen during combustion, high temperatures, can be reached. The general formula for alkynes CnH2a-2. These include acetylene: C2H2, propyne: Butin, and C3H4: C4H6.
Alkenes and alkynes, unsaturated hydrocarbons
The carbon atoms of hydrocarbons can be arranged in a circle.These cyclic hydrocarbons with single bonds are called cycloalkanes. Benzene and its derivatives are known as aromatic hydrocarbons. They contain double bonds. Benzene (benzene initially) was discovered in 1825 by M. Faraday. The name was coined by J. benzene von Liebig. Since benzene is not the alcohol, we call it benzene, benzene does not. Benzene is a colorless liquid, refraction of light and has an aromatic odor. This characteristic odor was the reason why benzene is a Grouparomatic compounds. Benzene is less dense than water and not mix with water. On the other hand, mix with or dissolve in nonpolar solvents. Benzene can also dissolve fats, resins and rubber. Its boiling point 80.1 ° C lower than that of water. At 5-6 ° C, benzene freezes and begins to crystallize. If it is burned, carbon soot, benzene releases. In its pure form, benzene dangerous for human health. When people are exposed to benzene for a long periodTime, their liver, kidneys and bone marrow. Benzene is a carcinogen, but it is a useful material for the chemical reagents in the synthesis of a series of organic compounds.
Cyclic hydrocarbons
Cyclic hydrocarbons can be differentiated from aliphatic hydrocarbons. The cycloalkanes, which are composed of several CH 2 groups and double bonds, form a homologous group of compounds. The first member is cyclopentane. The same as the next memberCyclohexane, is very unstable. Why are saturated cycloalkanes compounds, such as linear alkanes are not very reactive. They also share a set of properties. The aromatic hydrocarbons benzene. The members of the group have six valence electrons, which are distributed in a circle, in the form of a cloud charge. Due to the presence of valence electrons, we can predict that the reactivity of these aromatic compounds are similar to other unsaturated hydrocarbons.This time, however, our prediction is wrong: benzene is much less reactive than other unsaturated hydrocarbons. Only at high temperatures and benzene in the presence of a catalyst to take another atom of hydrogen. If this happens, the resulting product is cyclohexane.
The molecular structure of benzene and cyclohexane
Benzene (benzene), which was already discovered in 1825, has been described by FA Kekule von Stradonitz for the first time in 1865. After the description of Kekule,Benzene is a compound with six carbon atoms move. Benzene ring containing three double bonds alternating with three single bonds. Kekule believed that these double bonds are fixed in one place in the molecule. He thought that there are two isomers of benzene, which side by side.
Modern models of structure of benzene each carbon atom to it an unpaired electron, a free electron. These unpaired electrons are shared in the circleForms a cloud charge. Do not have a specific position in the formation of double bonds. This arrangement of electrons is odd mezomeric. And 'why benzene is not as responsive as you might expect, compared to other compounds that contain double bonds.
Cyclohexane is a cyclic hydrocarbon family-related connections between the individual carbon atoms. It consists of six carbon atoms, each consisting of two hydrogen atoms connected to it.
Noble gases,Halogenated alkanes
The noble gases are in Group VIII of the main elements of the group, found in groups. They have a full outer electron shells and are therefore almost non-responsive. The lighter noble gases are the links to all, and only a handful of the most severe form that formed in place, and exist only under certain conditions. The elements of the group of noble gases are helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe) and radon (Ra). All over the nextGaseous phase of matter. And 'possible to produce them by the distillation of liquid air (at a temperature of about -200 ° C).
The noble gases are not flammable. Balloons and other balloon is used because it is lighter than air. Radon is a product of the reaction of cleavage of the radio radioactive element. The other noble gases are used in many types of lighting, because they do not respond (light bulbs, fluorescent tubes).
Halogens are inseventh main group elements. They have seven electrons in their outermost electron shell. May react with other elements and covalent bonds as well as the ability to react to form ionic bonds. They occur in nature in compounds. Small halogen, which are at the top of the periodic table, more reactive halogens in the bottom of the table, so that the smaller halogen can take the place of greatest compounds to replace it or replace it. All the halogensare poisonous. Fluorine (F), chlorine (Cl), bromine (Br), iodine (I) and astatine (At): the halogens. Fluorine and chlorine are gases at room temperature. Fluorine attacks and corrodes most other materials, like glass. Chlorine is very toxic. Halogens are either liquids or solids at room temperature, because of their size, where halogens are the largest solid. Gaseous state of the halogens are highly toxic.
Substitution rule
The replacement ofHalogens with alkanes is another way to burn more than you can react. In a substitution reaction, a hydrogen atom, a halogen atom is replaced. This type of reaction is as halogenation. The halogenation of alkanes occurs in the presence of light, making it a photochemical reaction.
Methane (C2H4) reacts with chlorine (which looks like a molecule with two atoms Cl2) to produce in the presence of light to form methyl chloride, CH3Cl and hydrochloric acid (HCl).
ThisConnections based on various criteria can be distinguished from each other:
1 The type of halogen such as fluorine, chlorine, bromine and iodine.
2 The type of carbon chain: open, closed, aromatic, saturated, unsaturated.
3 The number of atoms in the halogen: mono-, di-and poly-halogenated compounds.
The name of the compound by the number of carbon atoms, and where the replacement occurred halogen for a hydrogen atom. First nameHydrocarbons replaced the names of the halogens are listed in alphabetical order, if possible. Each carbon atom is a number, so that the halogen-substituted at the lowest possible number as allocated space. Then the number of carbon, which moved forward the halogen-prefix is defined. For example:
The carbon chain is always in such a way that the replacement of groups, numbers are assigned lower numbers. However, if there are more substitutions or a larger groupwas replaced with a functional group, ie, has the lowest number possible.
Fluorine is the first of the group halogen, which means it is replaced in the position for all other halogens in a chemical bond. For this reason, the fluorine-containing hydrocarbons is very stable, nonflammable and nontoxic. They are used as an ingredient in a spray or as a coolant in refrigerators, and as a solvent. Their use has become less popular in recent yearsYears because of the damage they do to the atmosphere, the ozone layer.
