C4H8 belongs to the homologous series of

The molecular formula C4H8 corresponds to the homologous series of alkenes. Hydrocarbons are classified based on their bonding and general formulas. Alkanes are saturated hydrocarbons with the general formula CnH2n+2; for four carbon atoms (n=4), the alkane butane is C4H10 [2][3]. Alkenes are unsaturated hydrocarbons containing at least one carbon-carbon double bond, following the general formula CnH2n [1][3]. Substituting n=4 into this formula yields C4H8, which is the molecular formula for butene [1]. In contrast, alkynes contain triple bonds and follow the formula CnH2n-2, which for n=4 would be C4H6 [3]. While cycloalkanes also share the CnH2n formula, the standard homologous series associated with C4H8 in introductory organic chemistry is the alkene series. Therefore, C4H8 is identified as an alkene [1].

Sources

1. [2] Science , class X (NCERT 2025 ed.) > Chapter 4: Carbon and its Compounds > 4.2.2 Chains, Branches and Rings > p. 64
2. [3] Science , class X (NCERT 2025 ed.) > Chapter 4: Carbon and its Compounds > Figure 4.10 Structure of benzene > p. 65
3. [1] Science , class X (NCERT 2025 ed.) > Chapter 4: Carbon and its Compounds > 4.2.4 Homologous Series > p. 66