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Question
The general molecular formula for the homologous series of alkynes is _______.
Options
CnH2n
`"C"_"n""H"_("2n" + 2)`
`"C"_"n""H"_("2n" - 2)`
`"C"_"n""H"_("2n" - 1)`
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Solution
The general molecular formula for the homologous series of alkynes is `underline("C"_"n""H"_("2n" - 2))`.
RELATED QUESTIONS
Write the next homologue of the following: C2H4
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| General formula | IUPAC name of the homologous series | Characteristic bond type | IUPAC name of the first member of the series |
| CnH2n−2 | (A) ______ | (B) ______ | (C) ______ |
| CnH2n+2 | (B) ______ | (E) ______ | (F) ______ |
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The molecular formula of a homologue of butane is ______.
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(a) What is compound A?
(b) Write the electron-dot structure of A.
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I. Potato and sweet potato are analogous organs in plants.
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| 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 |
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C3H8 belongs to the homologous series of ______.
Which of the following does not belong to the same homologous series?
Name the following organic compound:
The first homologue whose general formula is CnH2n.
Study and complete the following table:
| Homologous series | Alkane | Alkyne |
| General formula | CnH2n+2 | 1. ______ |
| IUPAC name | 2. ______ | Ethyne |
| Common name | Marsh gas | 3. ______ |
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(i) CH3COOH (ii) CH3OH (iii) C2H6 (iv) C3H4 (v) C4H8
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- Identify the compound having triple bond between carbon-carbon atoms.
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Name the third homologue of alcohols.
