FUNCTIONAL GROUPS IN CARBON
- Functional groups are specific substituents within molecules that are responsible for the characteristic chemical reactions of those molecules.
- Carbon also forms bonds with other elements (HETERO ATOM) such as halogens, oxygen, nitrogen and sulphur.
- In a hydrocarbon chain, one or more hydrogen’s can be replaced by these elements, according to their valency.
- A series of compounds in which the same functional group substitutes for hydrogen in a carbon chain is called a homologous series.
- As the molecular mass increases in any homologous series, changes in physical properties are seen the melting and boiling points increase with increasing molecular mass.
- A physical property such as solubility in a particular solvent also varies.
- The chemical properties remain similar in a homologous series because they are decided by functional group present in the series.
Nomenclature of carbon
IUPAC- INTERNATIONAL UNION OF PURE AND APPLIED CHEMISTRY
MAIN CHAIN- ROOTWORD +PRIMARY SUFFIX+ SECONDARY SUFFIX
- ROOTWORD- IT is name of number of carbon atom
- C1- meth C5- pent
- C2- eth C6- hex
- C3- prop C7- hept
- C4- but C8- oct
Naming a carbon compound can be done by the following method
- Identify the number of carbon atoms in the compound and select the possible longest chain, bearing functional group if present.
- In case a functional group is present, it is indicated in the name of the compound with either a prefix or a suffix.
- If the name of the functional group is to be given as a suffix,
- Propane – ‘e’ = propan + ‘one’ = propanone. (Delete the end “e” if the functional group starts with a vowel
- If the carbon chain is unsaturated, then the final ‘ane’ in the name of the carbon chain is substituted by ‘ene’ or ‘yne’.
- When two or more same substituents are present, numerical prefixes di, tri, tetra, or cyclo etc are used before the name of such substituents.