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Question
Define a homologous series. Give the name and structural formula of one homologue of the following:
CH3OH
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Solution
Homologous series: A series of organic compounds having similar structures and chemical properties and in which the successive compounds differ by -CH2 group is called a homologous series. A homologue of CH3OH will differ by the -CH2 group; therefore, methanol's successive homologue will be ethanol (C2H5OH).
The structural formula of ethanol is as follows:

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RELATED QUESTIONS
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Cyclohexane : Cyclic hydrocarbon : : Isobutylene : _______
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| Name | Molecular formula | Condensed structural formula | Number of carbon atom | Number of -CH2- units | Boiling point °C |
| Methanol | CH4O | CH3-OH | 1 | 1 | 63 |
| Ethanol | C2H6O | CH3–CH2-OH | 2 | 2 | 78 |
| Propanol | C3H8O | CH3–CH2–CH2-OH | ______ | ______ | 97 |
| Butanol | C4H10O | CH3–CH2–CH2–CH2–OH | ______ | ______ | 118 |
Name the following organic compound:
The first homologue whose general formula is CnH2n.
