A series of compounds with the same functional group and chains of sequentially increasing length is called a:

1. Compounds like CH3OH, CH3CH2OH and CH3CH2CH2OH share the -OH group but have different chain lengths. 2. Their chemical properties are similar because the functional group is the same. 3. Such a series with increasing chain length is called a homologous series. _Source: Balbharati (Maharashtra Board) Class 10 Science & Technology, Ch 9 "Carbon Compounds", p.127_