The chemistry of carbon ~
第1页/共1页
The chemistry of carbon ~
What constitutes Organic Chemistry?
The nature of Organic Chemistry has changed greatly since 1828. Before that time the scientific philosophy known as "Vitalism" maintained that Organic Chemistry was the chemistry of living systems. It maintained that Organic Compounds could only be produced within living matter while Inorganic compounds were synthesized from non-living matter. Even the word "organic" comes from the same root as the word "organism" or "organ". However people like Professor Wohler beginning in 1828 determined that it was indeed possible to synthesize organic compounds from those compounds that were considered inorganic. One of the first organic compounds synthesized from basically inorganic compounds was the compound Urea which is a metabolic product of urine. It was synthesized from Ammonium Cyanate considered a compound produced outside of living matter and therefore considered inorganic. Since then many millions of Organic compounds have been synthesized "in vitro" in other words outside living tissue.
Organic Chemistry has developed into a branch of Chemistry that focuses upon the carbon containing compounds. It has just recently been expanded to include compounds of Silicon since Silicon is similar in behavior to Carbon being in the same group within the Periodic Table. Given that the main material in which micro-chips of the computer age have as their foundation is Silicon, it is fitting that the main element establishing living organisms should be merged with the main element involved in the inanimate machine world.
The nature of Organic Chemistry has changed greatly since 1828. Before that time the scientific philosophy known as "Vitalism" maintained that Organic Chemistry was the chemistry of living systems. It maintained that Organic Compounds could only be produced within living matter while Inorganic compounds were synthesized from non-living matter. Even the word "organic" comes from the same root as the word "organism" or "organ". However people like Professor Wohler beginning in 1828 determined that it was indeed possible to synthesize organic compounds from those compounds that were considered inorganic. One of the first organic compounds synthesized from basically inorganic compounds was the compound Urea which is a metabolic product of urine. It was synthesized from Ammonium Cyanate considered a compound produced outside of living matter and therefore considered inorganic. Since then many millions of Organic compounds have been synthesized "in vitro" in other words outside living tissue.
Organic Chemistry has developed into a branch of Chemistry that focuses upon the carbon containing compounds. It has just recently been expanded to include compounds of Silicon since Silicon is similar in behavior to Carbon being in the same group within the Periodic Table. Given that the main material in which micro-chips of the computer age have as their foundation is Silicon, it is fitting that the main element establishing living organisms should be merged with the main element involved in the inanimate machine world.
回复: The chemistry of carbon ~
Families of Organic Compounds
Organic Chemistry is the largest branch and fastest growing branch of Chemistry. Generally Organic Chemistry is manageable by classifying organic compounds into "families". Each family consists of compounds that have a chemically active center of the molecule called the family's "functional group". All members of a particular family have similar Chemistry because their functional group is the center of Chemical activity.
Organic Chemistry is the largest branch and fastest growing branch of Chemistry. Generally Organic Chemistry is manageable by classifying organic compounds into "families". Each family consists of compounds that have a chemically active center of the molecule called the family's "functional group". All members of a particular family have similar Chemistry because their functional group is the center of Chemical activity.
回复: The chemistry of carbon ~
Alkanes
Alkanes are hydrocarbons that contain only single bonds. When carbons double back on one another to form a ring, they are called cycloalkanes. Alkanes are generally unreactive, and have the purpose of holding reactive functional groups, or the nonalkane portion of a molecule.
Since we generally don't care about the non-reactive portions of molecules, Organic Chemists often use the symbol R to represent alkyl substituents.
could be drawnindicate that the straight chain portion of the molecule is unimportant.
Nomenclature of Alkanes:
Naming of organic structures, unlike biological classification, follows a rigid set of rules. The International Union of Pure and Applied Chemistry, abbreviated IUPAC, came up with a set of rules that follows the same standards worldwide, and is accepted among all chemists. However, common names of compounds, or names that have historical roots, are still used today for many compounds.
IUPAC Name: Propanone
Common Name: Acetone
For a base of one to four carbons, historical root names were chosen. For compounds of five carbons and up, the greek name for the number of carbons is used. The ending of -ane is added to indicate that it is an alkane.
Number of Carbons Prefix
1 Methane
2 Ethane
3 Propane
4 Butane
5 Pentane
6 Hexane
7 Heptane
Alkanes are hydrocarbons that contain only single bonds. When carbons double back on one another to form a ring, they are called cycloalkanes. Alkanes are generally unreactive, and have the purpose of holding reactive functional groups, or the nonalkane portion of a molecule.
Since we generally don't care about the non-reactive portions of molecules, Organic Chemists often use the symbol R to represent alkyl substituents.
could be drawnindicate that the straight chain portion of the molecule is unimportant.
Nomenclature of Alkanes:
Naming of organic structures, unlike biological classification, follows a rigid set of rules. The International Union of Pure and Applied Chemistry, abbreviated IUPAC, came up with a set of rules that follows the same standards worldwide, and is accepted among all chemists. However, common names of compounds, or names that have historical roots, are still used today for many compounds.
IUPAC Name: Propanone
Common Name: Acetone
For a base of one to four carbons, historical root names were chosen. For compounds of five carbons and up, the greek name for the number of carbons is used. The ending of -ane is added to indicate that it is an alkane.
Number of Carbons Prefix
1 Methane
2 Ethane
3 Propane
4 Butane
5 Pentane
6 Hexane
7 Heptane
回复: The chemistry of carbon ~
Physical Properties of Organic Compounds
In general, covalent organic compounds are distinguished from inorganic salts by low melting points and boiling points.
The ionic compound sodium chloride (NaCl), for example, melts at about 800° C (about 1470° F), but the strictly covalent molecule, carbon tetrachloride (CCl4), boils at 76.7° C (170° F). Between these temperatures an arbitrary line may be drawn at about 300° C (about 570° F) to distinguish most covalent from most ionic compounds. A large fraction of organic compounds melt or boil below 300° C, although exceptions exist. Organic compounds generally dissolve in nonpolar solvents (liquids that do not have localized electric charges) such as gasoline or carbon tetrachloride, or solvents of low polarity such as alcohols, acetic acid, and acetone. Organic compounds are often insoluble in water, a strongly polar solvent.
Hydrocarbons have low densities, often about 0.8 compared to water, 1.0, but functional groups may increase the densities of organic compounds to 1.0. Only a few organic compounds have densities greater than 1.2, generally those containing multiple halogen atoms.
Functional groups capable of forming hydrogen bonds generally increase viscosity (resistance to flow) in molecules. For example, the viscosities of ethanol, ethylene glycol, and glycerol increase in that order. These compounds contain one, two, and three OH groups, respectively, which form strong hydrogen bonds.
In general, covalent organic compounds are distinguished from inorganic salts by low melting points and boiling points.
The ionic compound sodium chloride (NaCl), for example, melts at about 800° C (about 1470° F), but the strictly covalent molecule, carbon tetrachloride (CCl4), boils at 76.7° C (170° F). Between these temperatures an arbitrary line may be drawn at about 300° C (about 570° F) to distinguish most covalent from most ionic compounds. A large fraction of organic compounds melt or boil below 300° C, although exceptions exist. Organic compounds generally dissolve in nonpolar solvents (liquids that do not have localized electric charges) such as gasoline or carbon tetrachloride, or solvents of low polarity such as alcohols, acetic acid, and acetone. Organic compounds are often insoluble in water, a strongly polar solvent.
Hydrocarbons have low densities, often about 0.8 compared to water, 1.0, but functional groups may increase the densities of organic compounds to 1.0. Only a few organic compounds have densities greater than 1.2, generally those containing multiple halogen atoms.
Functional groups capable of forming hydrogen bonds generally increase viscosity (resistance to flow) in molecules. For example, the viscosities of ethanol, ethylene glycol, and glycerol increase in that order. These compounds contain one, two, and three OH groups, respectively, which form strong hydrogen bonds.
回复: The chemistry of carbon ~
Ether
Ethers are molecules with one or more C-O-C groups
Line structure
Example: Diethyl ether, an anesthetic
Ethers are molecules with one or more C-O-C groups
Line structure
Example: Diethyl ether, an anesthetic
回复: The chemistry of carbon ~
isomers
Structural isomer
Stereoisomers
Stereoisomers are isomers where the atoms are connected in the same way in the molecules (unlike structural isomers) but the geometry of the atoms in space is different. There are two types
Geometric isomers
Optical isomers
Structural isomer
Stereoisomers
Stereoisomers are isomers where the atoms are connected in the same way in the molecules (unlike structural isomers) but the geometry of the atoms in space is different. There are two types
Geometric isomers
Optical isomers
第1页/共1页
您在这个论坛的权限:
您不能在这个论坛回复主题