Chemistry / Unit 12 Chem 2442 short lesson, about 20 seconds
Alkenes: Restricted Rotation at the Double Bond
Captions available
The idea
An alkene contains a carbon-carbon double bond, each sp2 carbon trigonal planar, rotation around the bond restricted since it would break the pi bond.
In practice
Ethene's carbons and hydrogens all lie in one plane, held rigid by the double bond's pi bond.
Where people slip
A nearby single bond still rotates freely — the restriction applies only at the double bond, not the rest.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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