The incorrect statement regarding ethyne is:
Hydrocarbons · Class 11 · JEE Main Previous Year Question
The incorrect statement regarding ethyne is:
- a
The bond in ethyne is shorter than that in ethene.
- b
Both carbons are hybridised.
- c
Ethyne is linear.
- d✓
The carbon-carbon bond in ethyne is weaker than that in ethene.
The carbon-carbon bond in ethyne is weaker than that in ethene.
Step 1: Analyze Each Statement
(a) C-C bond in ethyne shorter than ethene? Triple bond length ~1.20 A vs double bond ~1.34 A. Shorter in ethyne. (a) CORRECT.
(b) Both carbons sp hybridised? Triple bond = sp hybridization. (b) CORRECT.
(c) Ethyne is linear? sp carbons give 180 degree bond angle. (c) CORRECT.
(d) C-C bond in ethyne weaker than in ethene? Triple bond (bond order 3) is stronger than double bond (bond order 2). Bond energy: C≡C ~835 kJ/mol vs C=C ~612 kJ/mol. (d) INCORRECT -- triple bond is stronger, not weaker.
Key Points:
- Higher bond order = shorter bond length AND stronger bond
- Ethyne triple bond is both shorter and stronger than ethene double bond
Practice this question with progress tracking
Want timed practice with adaptive difficulty? Solve this question (and hundreds more from Hydrocarbons) inside The Crucible, our adaptive practice platform.
More JEE Main Hydrocarbons PYQs
The alkane from below having two secondary hydrogens is:
In the following reaction, 'X' is:
Arrange the following conformational isomers of n-butane in order of their increasing potential energy:
Identify A in the given chemical reaction.
Which of the following compounds produces an optically inactive compound on hydrogenation?