The word 'organic' means living. first organic chemisrty was the study of compunds from plants and animals. Now all the complex variety of compunds can be made artificially. Organic chemistry includes the study of synthetic compunds including polymers, drugs and dyes.
Chains and rings : this is how organic compunds are linked. In the organic compunds carbon is often linked to hydrogen, oxygen, nitrogen and halogen atoms.
Carbons form so many compunds because they can join up in many ways forming new chains, branches chains and rings. They can be very long as in the polymer polythene.
Bondng in carbon compunds
The bonding in organic compunds is covalent, the structures are molecular. Carbon atoms form 4 bonds, hydrogen atoms form 1 bond which oxygen atoms form 2 bonds.
The alkanes make up an important series of hydrocarbons. The simples alkane is methane. This is the main gas in natural gas.
The five alkanes:
Physical Propertiesof alkanes
The alkanes are oily. They do not dissolve in water or mix with it.
The alkanes with small molecules ( up to four carbon atoms) are gases at room tempereture.
The ones with 417 carbon atoms are liquids. the candle wax have molecules with more than 17 carbon atoms and these are solid at room tempereture.
Chemical Properties of alkanes.:
Burning : All alkanes burn, many common fuels consists mainly of alkanes.
The hydrocarbons burn in air, forming carbon dioxide and water.
Reactions with aqueous acids and alkalis:
alkanes DO NOT react with common laboratory reagents such as acids and alkalis. The hydrocarbons do not react because the C-C and C-H bonds in the molecules are UNREACTIVE.
Uses of alchohols:- Ethanol is the best known member of the series of alchohols.
Ethanol is a very useful solvent, it is liquid that evaparates quickly, and for this reason it is used in cosmetic lotions and perfumes, it easily catches fire and burns with a clean flame so it can be used as a fuel.
The simplest alcohol, methanol can be made in two steps from methane (natural gas) and steam.