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प्रश्न
The first member of alkyne homologous series is
पर्याय
ethyne
ethene
propyne
methane
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उत्तर
ethyne
Explanation -
The general formula for an alkyne is CnH2n-2. So, the first member of this series is C2H2 (ethyne).
APPEARS IN
संबंधित प्रश्न
Write the name and formula of the 2nd member of homologous series having general formula CnH2n + 2.
Write the molecular formula of the 2nd and 3rd member of the homologous series where the first member is ethyne.
What is the next higher homologue of methanol (CH3OH)?
Write the names and formulae for the first three members of the homologous series of chloroalkanes.
What is a homologous series? Explain with an example.
The molecular formula of an organic compound is C18H36. Name its homologous series.
Propane and ethane are ______.
Give the names and the structural formula of the first three members of the homologous series of alkanes.
Write the name and formula of the fourth member of the following homologous series:
Alkyne
Assertion (A): In a homologous series of alcohols, the formula for the second member is C2H5OH and the third member is C3H7OH.
Reason (R): The difference between the molecular masses of the two consecutive members of a homologous series is 144.
The unsaturated hydrocarbons containing a carbon-carbon double bond are called _______.
While going in an increasing order of the length there is a rise in the molecular mass of the members by ______.
The general molecular formula for the homologous series of alkynes is _______.
Saturated hydrocarbon : Single bond : : Unsaturated hydrocarbon : _______
Write a short note.
Homologous series
Complete the following table for homologous series of alcohols.
| 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 |
Complete the following table for homologous series of Alkenes.
| Name | Molecular formula | Condensed structural formula | Number of carbon atom | Number of -CH2- units | Boiling point °C |
| Ethene | C2H4 | CH2 = CH2 | 2 | 0 | -102 |
| Propene | C3H6 | CH3–CH = CH2 | 3 | 1 | -48 |
| 1-Butene | C4H8 | CH3–CH2–CH = CH2 | ______ | ______ | -6.5 |
| 1-Pentene | C5H10 | CH3–CH2–CH2–CH = CH2 | ______ | ______ | 30 |
Complete the following chart by using examples given in brackets.
(isobutylene, cyclohexane, propane, cyclohexene, cyclopentane, benzene, propyne, isobutane, propene)
| Straight chain hydrocarbons | Branched chain hydrocarbons | Cyclic hydrocarbons |
A carbon compound ‘A’ having melting point 156K and boiling point 351K, with molecular formula C2H6O is soluble in water in all proportions.
- Identify ‘A’ and draw its electron dot structure.
- Give the molecular formulae of any two homologues of ‘A’.
