Number of possible alkynes with formula $C_5H_8$ is
- 2
- 3
- 4
- 5
The Correct Option is B
Solution and Explanation
Top Questions on Alkynes
- The incorrect statement regarding ethyne is
The product of hydrolysis of propyne in the presence of 1% \( HgSO_4 \) and 40% \( H_2SO_4 \) is ___________.
- General formula of alkynes
The structures of major products A , B and C in the following reaction are sequence
- The correct order of acidic nature of the following alkynes is:
I. \( \text{C}_2\text{H}_2 \)
II. \( (\text{CH}_3)_2\text{C}_2 \)
III. \( (\text{CH}_3)\text{C}_2\text{H} \)
Questions Asked in KCET exam
A block of certain mass is placed on a rough floor. The coefficients of static and kinetic friction between the block and the floor are 0.4 and 0.25 respectively. A constant horizontal force \( F = 20 \, \text{N} \) acts on it so that the velocity of the block varies with time according to the following graph. The mass of the block is nearly (Take \( g = 10 \, \text{m/s}^2 \)):
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Concepts Used:
Alkynes
In organic chemistry, an alkyne is an unsaturated hydrocarbon containing at least one carbon-carbon triple bond. Alkynes are an organic molecule that contains triple bonds between the carbon atoms. Its general formula is CnH2n-2. They are also known as acetylenes. In this article, we will deal with the structure of alkynes.
Isomerism in Alkynes:
Alkynes show three types of isomerism
- Chain isomerism - Due to the different arrangement of carbon atoms in the chain that is straight chain or branched.
- Position isomerism - Due to the difference in the location of the triple bond.
- Functional isomerism - Isomeric with alkadienes both being represented by the general formula CnH2n-1.
Properties of Alkynes:
Physical Properties:
- Non-polar, unsaturated hydrocarbons.
- Highly soluble in organic and non-polar solvents and slightly soluble in polar solvents.
- High boiling point, in comparison to other hydrocarbons.
- Release a high amount of energy due to the repulsion of electrons in a reaction.
- More acidic than alkanes and alkenes due to SP hybridization.
Chemical Properties:
- Hydrogenation - Alkynes undergoes two types of hydrogenation reactions. Complete hydrogenation (in presence of Pd-C/ H2) and partial hydrogenation (in presence of Linder’s catalyst/H2).
- Act as a strong nucleophile by converting into acetylide.
- React with BH3 and undergo hydroboration reactions to form aldehydes and ketones.
- Undergo halogenation reactions in the presence of different halogenating agents by different mechanisms and forms haloalkanes.