Question

Whichof the following is not the

property of homologous series?

(a) They differ by-CH2 units

(b) They differ by-14 units by mass

(c) They all contain double bond

(d) They can be represented by a

general formula​

Answer 1

Answer:

c) they all contain a double bond

Answer 2

The correct option is c.

• Homologous series differ by a $-CH_2$ unit from the next member of the series.
• The atomic weight of the C atom is 12 units and the H is 1 unit. Thus, the mass of $-CH_2$ is 12+2×1=14 units. So, the members of the homologous series differ by 14 units by mass.
• They all do not contain double bonds.
• They can be represented by a general formula. Like alkene homologous series is given by $C_nH_{2n}$.