The molecular formula of a hydrocarbon is C6 H8, what would be the molecular formula and name of the next member in this homologous series?
Answers
Answer:
(a) Homologous series is defined as a systematic order of organic compounds having same functional group that can be represented by same general formula and prepared by same method.
Each member of a homologous series is known as homologue and this phenomenon is called homology. Properties of homologous series are:
1. Two consecutive members of a homologous series differs each other in their composition by –CH
2
unit.
Example:Alcohol (−OH)−CH
3
OH,CH
3
CH
2
OH,CH
3
CH
2
CH
2
OH
2. The members of a homologous series can be represented by same general formula. Example:Alcohol C
n
H
2n+1
OH
3. The members of a particular homologous series have almost same chemical properties due to presence of same functional group.
(b) In organic chemistry, an alkene is an unsaturated hydrocarbon that contains at least one carbon–carbon double bond. They form a homologous series of hydrocarbons with the general formula C
n
H
2n
. Alkynes are a series of unsaturated hydrocarbons containing atleast one triple bond. They forma a homologous series of hydrocarbons with the general formula C
n
H
2n−2
. So according to this, (iii) is alkene and (ii) is alkyne.
