Halogenoalkanes 3.3.3 Flashcards
What reagent would be needed for the nucleophilic substitution of OH- ?
aqueous NaOH or KOH
What condition would be needed for the nucleophilic substitution of OH- ?
warm mixture
What reagent would be needed in the nucleophilic substitution of CN- ?
aqueous alcoholic solution of KCN
What reagent would you need in the nucleophilic substitution of NH3 ?
concentrated ammonia in ethanol
What condition would the nucleophilic substitution of NH3 need to be in?
excess ammonia
What reagent would be needed in the elimination reaction of a haloalkane to an alkene
NaOH or KOH in ethanol
What condition do elimination reactions have to be in ?
Heat
How do we know if OH- acts as a base (and eliminate) ?
OH- in the ethanolic solution (dissolved in ethanol) and high temperature favours elimination reactions
How do we know if OH- acts as a nucleophile ( and substitute)?
OH- in the aqueous solution and room temperature favour substitution reactions
What is the initiation step to explain how chlorine atoms catalyse decomposition of ozone?
CCl3F => •CCl2F + •Cl
What is the propagation step to explain how chlorine atoms catalyse decomposition of ozone ?
Cl• + O3 => ClO• + O2
ClO• + O3 => 2O2 + Cl•
How do chlorine atoms damage the ozone layer?
Chlorine atoms catalyse the decomposition of the ozone and contribute to the hole in the ozone layer
What do we use instead of chlorofluorocarbons (CFC) and why?
hydrofluorocarbons ( HFC) because they do not contain chlorine so no chlorine free radicals which can damage the ozone layer
What does the ozone layer do in our atmosphere?
The ozone layer protects us from UV radiation (can cause skin cancer)
What nucleophilic substitution reactions are there?
Haloalkane => alcohol (-OH)
Haloalkane => nitrile (-CN)
Haloalkane => amine (NH3)
