Chemistry Hydrocarbons PMDC Conceptual Practice
PMDC Verified Question 1 of 65
Ethene has pi bonds? [None listed in source, derived structural query]
A
2
B
3
C
4
D
1
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option D: 1
Concept:

The double bond in organic molecules consists of exactly one strong sigma bond and one weaker pi bond.

Solution:

  • Ethene (\( \text{H}_2\text{C}=\text{CH}_2 \)) contains a carbon-carbon double bond.


  • The first connection between any two atoms is always a sigma (\( \sigma \)) bond formed by head-to-head orbital overlap.


  • The second connection is formed by the lateral (sideways) overlap of unhybridized p-orbitals, which is the pi (\( \pi \)) bond.


  • Therefore, ethene has exactly 1 pi bond.


Why other options are incorrect:

  • 2 pi bonds are present in a triple bond (alkynes).


  • Options of 3 and 4 pi bonds far exceed the valency limits of a simple carbon-carbon connection.

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