Homologous series

It is defined as series of similarly, constituent compounds having same functional group and same chemical properties, and they differ by CH₂ group and atomic mass by 14 a.m.u .

IUPAC system (Geneva system)

It is international union of pure & applied Chemistry. This system was introduced in 1947 revised in 1933.According to this name of compound consist of 3 parts that is:

Prefix  WordRoot  Suffix

Word root: ( Organic Chemistry )

Suffix:

Suffix  two types:- 1. Primary (Indicates the bond)

2. Secondary (Indicates the functional group)

Primary Suffix

• Indicate the type of bond between Carbon atoms like:
• Single Bond(ane)
• Double Bond(ene)
• Triple Bond(yne)
• If two or three double or triple bond or present so, they are named as di, tri, tert etc.

 Secondary suffix

• Indicate the functional group

Note: While adding secondary suffix to primary suffix ‘e’ of primary suffix is dropped, if sec suffix begins with vowel.

Prefix:

 Indicate substituent present in compound.

They can be

• Alkyl group’s (which have one Hydrogen less than alkane).

                Example:- CH₃– methyl , C₂H₅ – Ethyl

• Functional group – If more than two functional groups are present, than one is treated as main functional group and other as substituent. The prefix used for functional groups are:

F = Fluoro 

Cl = Chloro

Br = Bromo

I = Iodo

NO₂⁺ = Nitro

NH₂^– = Amino

NO = Nitro

N=N = Diazo

OCH₃ = Methoxy

OC₂H₅ = Ethoxy

OH = Hydroxy

Different Type of Organic Compounds

1. Hydrocarbon

They are of two types:

• Saturated
• Unsaturated

Saturated: They are called as Alkanes (paraffins) with general formula C_nH_2n+2

 Unsaturated: They are also called as olefins. They may be –

• Alkenes (general formula C_nH_2n).
• Alkynes (general formula C_nH_2n-2.).

1⁰ = If carbon atom is joined one other Carbo atom(primary)

2⁰ = If carbon atom is joined two other Carbo atom(secondary)

3⁰ = If carbon atom is joined three other Carbo atom(tertiary)

4⁰ = If carbon atom is joined four other Carbo atom(quaternary)

 Alkyl halides (Haloalkanes)                                                

Like in CH₄ the one Hydrogen atom is replaced by Halogen. So, it becomes CH₃Cl . The general name of it is Haloalkane.

Formula :- C_nH_2n+1(RX)