Question

Define the homologous series and find the common difference between the
successive members of this family. (CnH2n+2 is the general formula of a homologous series of hydrocarbons.)

Answer 1

"According to the organic chemistry, homologous series is a compound with the same chemical properties like carbon chains or CH2. Series of compounds with the same general formula is known as homologous series.

CnH2n+2 is a formula of alkanes and this is saturated hydrocarbons. Here all carbon atoms are bonded with the hydrogen atoms and this is a saturated formula of alkenes or paraffin. In homologous series the two consecutive members will differ by 14u or CH2 units. In case of alkanes (General Formula :

CnH2n+2).

Example methane and ethane.

CH4 , C2H6, C3H8

Molecules masses are 16, 30, 44

Consecutive ones differ by 14.

So each of them differs by -CH2 units.

"