Question

methane ethane and propane are set to form a homologous series because all are​

Answer 1

• hydrocarbons
• saturated compounds
• aliphatic compounds

Answer 2

There is a difference of one methylene group between the consecutive members of the given series of methane, ethane, and propane which makes it a homologous series.

• A homologous series consists of the members of the same general formula but differ by a methylene group(-CH₂-).
• Methane, ethane, and propane are all alkanes, with general formula $C_{n} H_{2n+2}$.
• The molecular formula of methane is $C H_{4}$ whereas ethane is $C_{2} H_{6}$.
• Propane is a three-carbon compound with a molecular formula $C_{3} H_{8}$.
• Ethane has a $-CH_{2}-$ group more than methane and one  $-CH_{2}-$ group less than propane.
• Hence, they form a homologous series.