Elimination Reactions

In elimination reactions, single bond molecules (alkanes), becomes double bond molecules (alkenes), giving off a smaller molecule.
So this the removal of a molecule from a larger one.
"alkane → alkene + something"

DEHYDROHALOGENATION
de-hydro-halogenation

removal of a halogen
HCl is removed form the organic molecule

Reaction Condition
• conc NaOH / KOH or
• NaOH / KOH dissolved in ethanol



Diagram 1

DEHYDRATION
de-hydration

removal of water H2O from the alcohol organic compound

Reaction Condition
• H2SO4
• hot catalyst



Diagram 2

CRACKING

breaking large alkanes into smaller alkenes and alkanes.
typically in the fuel industry

Reaction Condition
• Pt catalyst (platinum)
• 8000C


Diagram 3





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