Select the hydrocarbons which belong to the same homologous series. Give the name if of each series.

CH₄, C₂H₂, C₂H₄, C₂H₆, C₄H₁₀, C₃H₄, C₃H₆,

38 State two characteristics of a homologous series. 38 The molecular formula of an organic compound is C₁₈H₃₆. Name its homologous series. 38 What is meant by ‘heteroatom’? Give examples. Write the names and formulae of two organic compounds containing different heteroatoms. 39 What is meant by a functional group? Explain with an example.