The Concept Of Functional Groups In Organic Molecules And Homologous Series Flashcards
Functional group
Part of organic molecule responsible for it’s CHEMICAL BEHAVIOUR (reactivity)
Homologous series
*A family of related organic compounds with similar chemical structure
*A family of organic compounds that have the same functional group and belong to the same family
Characteristics of elements in a homologous series
*they are represented by a general molecular formular
*They are prepared by similar methods
*Each member has a relative molecular mass of 14 greater than the preceeding compound in the series
*Members of any homologous series exhibit a regular gradation of physical properties for example alkanes ..1-4 carbon atoms are gases at room temp
:Pentane(5 carbon atom) is a volatile liquid with a boiling point of 36°c
:The very high members are solids
:The melting point and boiling points of members of the alkane series is DIRECTLY PROPORTIONAL to the number of carbon atoms per molecule
What is the chemistry of the different classes of organic compounds
This is the chemistry of their functional group
Compared to the functional group of a compound, the rest of the molecules are ?
They are relatively inert
Functional group is also known as
The site of the reaction
What part of the organic compound goes into reactivity
The functional group
NB
Carbon does not participate in the reaction
Class of OC: alkanes
*General formular
*Functional group
CnH2n+2
Single bond hydrocarbon chain
Class of OC: alkenes (olefines)
General formular
Functional group
CnH2n
Double bond hydrocarbon chain
Class of OC: alkynes (acetylene)
General formular
Functional group
CnH2n-2
Thriple bond hydrocarbon chain
Class of OC: alkyl halides (Halogenoalkanes)
General formular
Functional group
R-X (X is for any halogen)
Or CnH2n+1-X
Halogen atom X
X= F,Cl,Br,I
Class of OC: alcohol (alkanols)
General formular
Functional group
R-OH or
CnH2n+1-OH
Hydroxyl group (-OH)
Class of OC: Ethers (alkoxyalkanes)
General formular
Functional group
R-O-R
C-O-C group
Class of OC: Nitriles(Cyanides)
General formular
Functional group
R-CN
Cyanide group
Class of OC: isocyanides(carbylamines)
General formular
Functional group
R-NC
The isocyanide group
Class of OC: Aldehydes(alkanals)
General formular
Functional group
RCHO
Aldehydic group
Class of OC: ketones(alkanones)
General formular
Functional group
R CO R
Carbonyl group (CO)
Class of OC: carboxylic group(alkanoic)
General formular
Functional group
RCOOH
Carboxylic group
Class of OC: Esters
General formular
Functional group
RCOOR
Ester group (COO)
Class of OC: amines
General formular
Functional group
R-NH2
Amino group
Class of OC: amides
General formular
Functional group
R-CONH2
Amide group
Class of OC: acid halides
General formular
Functional group
RCOX
acyl
Class of OC: acid anhydrides
General formular
Functional group
RCOOCOR
Anhydride group
Class of OC: Thioalcohols (thiols, mercaptons)
General formular
Functional group
R-SH
Thio(mercapto) group (-SH)
