Dr. SURENDRAN PARAMBADATH (M.Sc, M.Phil, M.Tech) Formerly: Post Doctoral Research Associate,Nano-Information Materials Research Laboratory, Pusan National University, Busan-South Korea Currently: Assistant Professor Govt. Polytechnic College, Perinthalmanna
Organic Compound Inorganic Compound1 Found in living organisms Found in non living matters-minerals2 Besides carbon they are compounds of H, They are composed of one or more of any O, N, S and P of the known elements.3 They are covalent compounds They are electrovalent compounds4 They are volatile and inflammable They are generally nonvolatile and non inflammable5 Generally insoluble in water and soluble in Soluble in water and insoluble in non polar non polar solvents, like benzene. solvents.6 Reaction involving organic compounds are Reaction is fast slow7 They exhibit isomerism Only coordination compounds exhibit isomerism8 They are non conductors of electricity Many of them conduct electricity in solution or fused form9 Their number is very large Small in number10 Generally, solids, liquids or gases Generally liquids or high melting solids.
The number of organic compounds is very large (~90%)Because:1. Catenation capacity2. Strength of C-C bond3. Tetra-covalency4. Capacity to combine with other non-metals like, H, O, N, S, P, Cl, Br, I etc.5. Possibility of multiple bonds and6. Isomerism
The tendency of an element to form chain of identical atoms iscalled catenation.Due to catenation, carbon atoms can form straight chains, branchedchains or closed chain compounds. C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C C
Compared to Si-Si, S-S, N-N or O-O bond C-Cbond is stronger and requires higher energy forbreaking.Hence chains with C-C bonds are stable.
Carbon atoms has four electrons in its valence shell andcan form four covalent bonds. This tetra-covalency orquadri covalency of carbon gives rise to variouspossibilities for formation of variety of structures. C C C C
Isomerism is the phenomenon in which one and the same molecularformula represents more than one compound with differentproperties.Due to directional character of covalent bonds different spacialarrangements and isomers are possible for compounds with thesame structural formula. CH3 H3C CH3 CH3 Trans-2-butene cis-2-butene
Organic compounds with only single covalent bondsbetween the carbon atoms are called saturatedcompounds. CH3-CH2-CH2-CH2-CH3In saturated compounds there will be no double ortriple bond between carbon atoms.In unsaturated compound, double or triple bondbetween carbon atoms. CH3-CH=CH-CH2-CH3
1. Unsaturated compounds decolorizes yellow colored bromine water.2. Baeyrs test: Unsaturated compounds decolorize alkaline potassium permanganate solution.Saturated UnsaturatedContain only single covalent bonds Contain at least one covalentbetween carbon atoms. double or triple bond between carbon atoms.Less reactive More reactiveDoes not decolorize bromine water Decolorize bromine water
Open Chain (Acyclic or aliphatic) CompoundsThese compounds contain an open chain of carbonatoms which may be a straight or a branched chain.CH3-CH2-CH2-CH3 CH3Normal butane (n-butane) Straight chain CH3-CH-CH3 Isobutane (iso-butane) Branched chain
Closed Chain (Cyclic or ring) CompoundsThese compounds contain one or more rings of carbon atoms.If the ring contains only carbon atom, it is called homocyclicring system.If it contains carbon and oxygen, nitrogen or sulphur it is calledheterocyclic ring system. Alicyclic Homocyclic Aromatic
Cyclopropane Cyclobutane Benzene N O O Oxazole Furan Naphthalene
Class of Nature of the Formula of the Example Organic functional functionalCompound group group Alkenes Double bond C=C Ethene Alkynes Triple bond -CC- Acetylene Alcohols Hydroxy -O-H MethanolAldehydes Aldehydic -CHO Acetaldehyde Group Acids Carboxyl -COOH Acetic acid Ethers Ether group -O- Diethyl ether Ketones Ketonic group -CO- Acetone Amines Amino group -NH2 Methyl amine Esters Ester group -COO- Methyl acetate
IsomerismTwo or more compounds having the samemolecular formula but different properties arecalled isomers and the phenomenon is calledisomerism.Structural: If the difference in properties of two isomersis due to difference in their structure, it is calledstructural isomerism.Stereo: If the isomers have the same structure butdifferent configuration it is called stereoisomerism.